beran 455 system

USER MANUAL FOR 455 SYSTEM

Document Number : Um455V100.DOC

Date : January 2001

Issue : 1.1.0

Raised : J Lovell

Approved :

DISCARD THIS SHEET PRIOR TO BINDING

Issue: 1.1.0 April 2001

USER MANUAL

for

455

VIBRATION TRANSDUCER

CALIBRATOR

Hatchmoor Ind Estate, Torrington, Devon, England, EX38 7HP

Telephone No: (+44) 01805 624304

Fax No: (+44) 01805 624093


Contents


455 USER MANUAL CONTENTS

1. INTRODUCTION AND GENERAL DESCRIPTION 1.1

1.1 Results Handling 2.2 1.2 Test Profile Generation 2.3 1.3 Measurement Traceability 2.3 1.4 Password Protection 2.3 1.5 Calibrating The 455 2.3 1.6 Accessories 2.4

2. SAFETY 3.1

2.1 Safety Terms and Symbols 3.1 2.2 Safety Precautions 3.1

3. INTRODUCING THE 455 SYSTEM 4.1

3.1 Introduction 4.1 3.2 Setting Up The Beran 455 System 4.1 3.3 Learning To Test 4.1

3.3.1 Loading Transducer Configuration 4.1 3.3.2 Entering Transducer Serial Number 4.2 3.3.3 Loading Reference Transducer 4.2 3.3.4 Loading Exciter Information 4.2 3.3.5 Loading Test Profiles 4.2 3.3.6 Starting The Tests 4.3 3.3.7 Displaying Test Results 4.3

3.4 Printing Results 4.3

4. INTRODUCING THE TRANSDUCER UNDER TEST MENU 5.1

4.1 Introduction 5.1 4.2 A Fictional Transducer 5.1 4.3 Configuring The Transducer 5.2

4.3.1 Entering the Transducers Menu 5.2 4.3.2 Data To Enter 5.2

4.4 Storing/Printing Transducer Configuration 5.2

5. INTRODUCING THE SETTING PROFILES MENU 6.1

5.1 Introduction 6.1 5.2 Programming A Frequency Step 6.1

Contents


5.3 Programming An Amplitude Step 6.1 5.4 Frequency Sweep Profile 6.2 5.5 Saving/Printing Profile Configurations 6.2

6. INTRODUCING THE REFERENCE MENU 7.1

6.1 Introduction 7.1 6.2 Information Required 7.1 6.3 Data To Be Loaded 7.3 6.4 How The Settings Should Look 7.3 6.5 Saving/Printing Reference Transducer Information 7.4

7. INTRODUCING THE UTILITIES MENU 8.1

7.1 Entering The Utilities Menu 8.1 7.2 Configure Exciter Sub-Menu 8.1 7.3 Example Shaker 8.1 7.4 External Test Hardware 8.3 7.5 Configure System 8.3 7.6 Save Setup 8.3 7.7 Additional Utilities 8.3

8. INSTALLATION AND OPERATING CONTROLS 9.1

8.1 Unpacking and Inspection 9.1 8.2 Introducing The Front Panel 9.1 8.3 QWERTY Keyboard 9.1 8.4 “Undo” Function 9.2 8.5 “Help” Function 9.2 8.6 Status Line 9.2 8.7 Principle of Operation 9.2 8.8 System Configurations 9.4

9. HARDWARE AND CONNECTION DETAILS 10.1

9.1 Mains Power Supply 10.1 9.1.1 Supply Voltage 10.1 9.1.2 Supply Power Cord 10.1 9.1.3 Inlet Fuse 10.1

9.2 Cleaning 10.1 9.3 Cooling 10.1 9.4 455 Rear Panel Connectors 10.2 9.5 Optional Rack Mounting 10.3

10. POWERING ON AND POWERING OFF THE 455 INSTRUMENT 11.1

Contents


10.1 Powering On 11.1 10.2 Status Line 11.1 10.3 Powering Off The 455 Instrument 11.1

11. USING THE MENUS 12.0

11.1 Finding the Correct Menu 12.0 11.1.1 Testing Menu 12.0 11.1.2 Transducers Menu 12.0 11.1.3 Profiles Menu 12.0 11.1.4 Reference Menu 12.0 11.1.5 Utilities 12.0

11.2 Selecting Menu Options 12.1 11.2.1 Entering Numeric Information 12.1

11.3 Connecting the 455 Controller 12.1 11.4 Restarting the Transducer Application 12.2

12. TEST MENU 13.1

12.1 Transducer 13.1 12.2 Serial Number 13.1 12.3 Transducer Information 13.1 12.4 Reference 13.1 12.5 Exciter 13.2 12.6 Operator 13.2

12.6.1 Operator Name 13.2 12.6.2 Temperature 13.2 12.6.3 Humidity 13.2 12.6.4 Air Pressure 13.3 12.6.5 Phase Measurement 13.3 12.6.6 Display From (Max. and Min Phase Angle Ranges) 13.3 12.6.7 Graph y-axis 13.3 12.6.8 Graph Zero At 13.3 12.6.9 Input Gain 13.4 12.6.10 High Pass Filter 13.4 12.6.11 Access Mode 13.4

12.7 Test Profiles 13.4 12.8 Running A Test Profile 13.5 12.9 Completion of Testing 13.5 12.10 Hardcopy 13.5 12.11 Error Messages 13.6

13. TRANSDUCERS MENU 14.1

13.1 List Known Transducers 14.1

Contents


13.2 Make New Transducer 14.1 13.3 Erase Transducer 14.1 13.4 Save Setup 14.1 13.5 Print Config 14.1 13.6 Manufacturer/Model Number 14.2 13.7 Transducer Information 14.2 13.8 Measured Parameter 14.2 13.9 Interface 14.2 13.10 Input Gain 14.3 13.11 Nominal Sensitivity 14.3

13.11.1 Nominal Sensitivity (Frequency) 14.3 13.11.2 Nominal Sensitivity (Amplitude) 14.3

13.12 Current Output Transducers 14.3 13.12.1 Current to Voltage 14.3

13.13 Operational Range 14.4 13.14 Mass 14.4 13.15 Frequency Range 14.4 13.16 Warm Up 14.4 13.17 Temperature Range 14.4 13.18 Cal Period 14.4

14. PROFILES MENU 15.1

14.1 List Known Profiles 15.1 14.2 Make New Profile 15.1 14.3 Erase Profile 15.1 14.4 Save Setup 15.1 14.5 Print Config 15.1 14.6 Profile Type 15.1

14.6.1 Frequency Step 15.2 14.6.2 Amplitude Step 15.2 14.6.3 Frequency Sweep 15.2

14.7 Control Parameter 15.2 14.8 Amplitude 15.2 14.9 Frequency 15.2 14.10 Table Editing 15.3

14.10.1 Insert Entry 15.3 14.10.2 Delete Entry 15.3 14.10.3 Re-Sort Entries 15.3

14.11 Frequency Range 15.3 14.12 Amplitude Range 15.3 14.13 Sweep Increment 15.3

15. THE REFERENCES MENU 16.1

15.1 List Known References 16.1

Contents


15.2 Make New Reference 16.1 15.3 Erase Reference 16.1 15.4 Save Setup 16.1 15.5 Print Config 16.1 15.6 Model Number 16.2 15.7 Serial Number 16.2 15.8 Measured Parameter 16.2 15.9 Interface 16.2 15.10 Current Output Reference Transducers 16.2

15.10.1 Current to Voltage 16.2 15.11 Nominal Sensitivity 16.2 15.12 Reference Table Editing 16.3

15.12.1 Frequency 16.3 15.12.2 Amplitude 16.3 15.12.3 Sensitivity 16.3 15.12.4 Phase 16.3 15.12.5 Insert Entry 16.4 15.12.6 Delete Entry 16.4 15.12.7 Re-Sort Entries 16.4

15.13 Operational Range 16.4 15.14 Payload 16.5 15.15 Frequency Range 16.5 15.16 Temperature Range 16.5 15.17 Last Calibrated / Cal Period 16.5

16. THE UTILITIES MENU 17.1

16.1 Configure Exciter 17.1 16.1.1 Exciter 17.1 16.1.2 List Known Exciters 17.1 16.1.3 Make New Exciter 17.1 16.1.4 Erase Exciter 17.1 16.1.5 Save Setup 17.1 16.1.6 Print Config 17.1 16.1.7 Exciter Description 17.2 16.1.8 Test Due 17.2 16.1.9 Frequency Range 17.2 16.1.10 Max. Acceleration 17.2 16.1.11 Max. Velocity 17.2 16.1.12 Max. Displacement 17.2 16.1.13 Soft Ramping 17.3

16.2 Configure Hardware 17.3 16.2.1 Last Cal 17.3 16.2.2 Cal Period 17.3 16.2.3 Conditioning 17.3 16.2.4 Test Due 17.4

Contents


16.2.5 Input Gain 17.4 16.2.6 High Pass Filter 17.4 16.2.7 Other Equipment 17.4 16.2.8 Test Due 17.4

16.3 Configure System 17.5 16.3.1 Settling Time or Cycles 17.5 16.3.2 Measurement Time or Cycles 17.5 16.3.3 Reference 17.5 16.3.4 Transducer 17.6 16.3.5 Phase Measurement 17.6 16.3.6 Display From (Max. and Min Phase Angle Ranges) 17.6 16.3.7 Graph Y Axis 17.6 16.3.8 Graph Zero At 17.6 16.3.9 Text Output 17.7 16.3.10 Device 17.7 16.3.11 Graph Output 17.7 16.3.12 Device 17.7 16.3.13 Disk Storage 17.8 16.3.14 Hardcopy Timeout 17.8 16.3.15 Prompt For Hardcopy 17.8 16.3.16 Sensitivity Displayed to ‘n’ Decimal Places 17.8 16.3.17 Disk Free Space 17.9 16.3.18 Date and Time 17.9

16.4 Save Set-Up 17.9 16.5 Additional Utilities 17.9

16.5.1 Access Codes 17.9 16.5.1.1 Operational Mode 1 17.9 16.5.1.2 Operational Mode 2 17.10 16.5.1.3 Configuration 17.10 16.5.1.4 Password Modification 17.10

16.5.2 Format Data Disk 17.10 16.5.3 Format Config Disk 17.10 16.5.4 Config Disk Copy 17.10 16.5.5 Copying 17.11

16.6 IEEE Slave Address 17.11

17. IEEE-488 REMOTE CONTROL 18.1

17.1 IEEE Address 18.1 17.2 IEEE Command Format 18.1 17.3 Parameter Formats 18.1 17.4 Generator Commands 18.2 17.5 Analyser Commands 18.2 17.6 Measurement Control Commands 18.3 17.7 Sweep Control Commands 18.3 17.8 Interface Control 18.4

Contents


17.9 Miscellaneous Commands 18.4 17.10 Enquiry Commands 18.4 17.11 Obtaining Results 18.5

17.11.1 Condensed Results Format 18.5 17.11.1.1 Output from the ?ODC command 18.5 17.11.1.2 Output from the ?ODP command 18.5

17.12 Obtaining Status Information 18.5 17.13 Serial and Parallel Polls 18.6

17.13.1 Serial Poll 18.6 17.13.2 Service Request 18.6 17.13.3 Parallel Poll 18.7

17.14 IEEE Command Errors 18.7 17.15 Example IEEE Control Program 18.7

18. REDUCING MEASUREMENT ERRORS 19.1

18.1 Test transducer Mounting 19.1 18.1.1 Mechanical Coupling 19.1 18.1.2 Triboelectric Effects 19.1

19. CALIBRATION 20.3

19.1 Measurement Circuits Calibration 20.3 19.1.1 Calibration Mode 20.4

19.1.1.1 Calibrate 20.4 19.1.1.2 Verify 20.4 19.1.1.3 Un-Calibrate 20.4

19.1.2 Automatic Calibration 20.4 19.1.2.1 Equipment Required 20.4 19.1.2.2 Automatic Calibration Method 20.5

19.1.3 Manual Calibration 20.5 19.1.3.1 Equipment Required 20.5 19.1.3.2 Manual Calibration Method 20.6

19.1.4 Result Hardcopy 20.6 19.1.4.1 Result Storage To PC Disk 20.6

19.2 Input Amplifier Calibration 20.7 19.2.1.1 Equipment Required 20.7 19.2.1.2 Calibration Method 20.7

20. INTERFACE CONNECTIONS 21.1

20.1 Serial Interface 21.1 20.2 Parallel Interface 21.1 20.3 Keyboard 21.1 20.4 Shaker 21.2

Contents


21. 455 SYSTEM SPECIFICATION 22.1

21.1 Generator 22.1 21.2 Shaker Output (Where different from generator) 22.1 21.3 Results 22.1 21.4 Measurement Channels 22.2 21.5 Transducer Test Profiles 22.4 21.6 Reference Transducer 22.4 21.7 Test Transducer 22.4 21.8 Interfaces 22.5 21.9 General 22.5

22. BERAN 455 TROUBLE SHOOTING GUIDE 23.1

Section 1 - 455 Introduction And General Description

Issue: 1.1.0 January 2001 Page: 1.1

1. About This Manual

This manual is intended as a guide to introduce the new user to the Beran 455Vibration

Transducer Calibration system and as a reference for the more advanced controls of the

instrument.

This manual is splint into two parts;

Part 1 includes sections 2 – 8 which give a basic overview of the instrument itself as

well as a ‘first-introduction’ guide to the operation of each of the primary configuration

menus, through the use of worked examples. These examples are accompanied by the

‘Beran 455 Getting Started Disk’, which has been supplied.

Part 2 includes sections 9 – 22 and covers the entire operation of the instrument.

Information contained within this part includes details of the systems operation,

examples of how to configure the system for a number of calibration set-ups and a full

function by function guide to each of the 455’s control parameters. Additional

information such as advice on how to reduce measurement errors and the calibration

procedure is also included.



2. Introduction And General Description

The Beran 455 Vibration Transducer Calibrator is used in conjunction with a calibration

shaker and reference transducer to form an automated calibration system.

The 455 Vibration Transducer Calibrator is a dedicated, high performance instrument, for the

fully automatic calibration of vibration transducers. The sine correlation measurement

technique is used in the 455 to ensure accurate, repeatable measurements are provided over a

wide frequency range and differing test conditions. The single 455, replaces the Power

Amplifier, Signal Conditioning, Signal Generator, Digital Voltmeter(s), Phase Meter,

Oscilloscope and Controlling Computer used in traditional vibration transducer calibration

systems.

The 455 system firmware is integral to the instrument with transducer and test configurations

stored to floppy disk. The instrument allows complete ‘Test Profiles’ to be generated and

performed, ensuring that a fully automatic calibration can take place with no operator

intervention.

The 455 instrument is fitted with integral precision signal conditioning amplifiers that allow

the automatic testing of Piezo Electric, Current Excitation, Voltage, and Current Output

Transducers. The amplifiers may be used to condition either a voltage, ICP or charge type

input and apply a gain of either x1, x10 or x100. An optional 5Hz HP filter may also be

applied if necessary. The configuration of the internal amplifiers may be set independently for

each test or reference transducer type and will be automatically applied upon the selection of

that transducer.

2.1 Results Handling

Transducer calibration results are displayed graphically at each test point of the active profile.

On completion of a profile, or sequence of profiles, the results may be viewed in either text or

graphical formats.

Via the 455’s standard RS232 and parallel interfaces, graphical and/or test results may be

directly output to hardcopy devices or colour pen plotters. Alternatively the results may be

stored to a PC format disk or sent via a serial link to a PC to allow exporting into

spreadsheets, word processors, calibration databases etc. HP-GL, PCL-5 and ASCII protocols

are supported to ensure a wide choice of hardcopy devices and PC software packages are

accessible to the 455.



2.2 Test Profile Generation

Generation of a new Frequency Step, Amplitude Step or Frequency Sweep test profile can be

achieved simply and quickly. A test profile name is entered along with the profile type, test

amplitude or frequency. If a frequency step or amplitude step test profile is selected, the

specific test frequencies and amplitudes are then entered. Amplitude information may be

entered in metric or imperial units with automatic conversion between. Further steps may be

added at a later date with a re-sort facility arranging the complete test in ascending frequency

/ amplitude order.

A Frequency Sweep test is simply defined with test program name, test amplitude, start and

stop frequency and a linear or logarithmic sweep increment.

2.3 Measurement Traceability

System measurement traceability is achieved by the use of a reference grade transducer

calibrated to the relevant national standards. The traceability is optimised by entering the

actual amplitude and phase deviations of the reference transducer at each calibration

frequency. This process is typically carried out annually and traceability is assured provided

the same frequencies are then selected during the calibration of each test transducer. An

automatic warning occurs if the user attempts to run a calibration test containing non-

traceable steps.

2.4 Password Protection

Two main levels of access are controlled by a password system to ensure shaker table safety,

calibration integrity and test profile repeatability.

Operational Access: Allows the user to select the transducer for test, run test profiles and

request certificate hardcopy and/or result storage to disk or PC. Prevents editing of test

profiles, reference transducer calibration values, shaker table safety parameters or the

measurement configuration.

Configuration Access: In addition to the above, the system manager is able to define test

profiles, enter reference transducer details, configure the system components and change the

access passwords.

2.5 Calibrating The 455

Full details of the instrument calibration procedure are given in the optional manual, ‘455

Vibration Transducer Calibrator – Calibration Procedure’



2.6 Accessories

The instrument is supplied with the following accessories:

Description Part No

Power Cable (Dependant Upon Country)

Set of Two Calibration Keys 319-770

User Manual UM455100

Getting Started 1.44MByte Floppy Disk FD-2577-01

Beran 455 Keyboard PL-2518-62

In addition the following accessories are available for use with the 455 instrument:

Description Part No

Rack Mounting Kit PL-2518-95

Shaker Output Mating Half Connector

Shaker Output to LDS V406 Lead PL-2577-90

LDS Type V406 Shaker LDS V406

Section 2 - Safety


3. SAFETY

This User Manual contains information and warnings / cautions which must be followed by

the user to ensure safe operation and to retain the equipment in a safe condition.

3.1 Safety Terms and Symbols

The following symbols are found on the instrument and in this Manual.

Functional Earth

(T) Slow Blow Fuse

(TT) Anti-Surge Fuse

CATII Insulation Category

The following user instructions are found in this Manual:

WARNING : Hazard that could cause personal injury or death.

CAUTION : Hazard that could cause damage to equipment

3.2 Safety Precautions

The following safety precautions should be observed using the 455 unit and any associated

instruments.

This instrument is intended for use by qualified personnel who recognise shock hazards and

are familiar with the safety precautions required to avoid possible injury. Read this manual

carefully before using the instrument.

Exercise extreme caution when a shock hazard is present at the test circuit. The American

National Standards Institute (ANSI) states that a shock hazard exists when voltage levels

greater than 30V RMS or 42.4V peak are present. A good safety practice is to expect that

hazardous voltage is present in any unknown circuit before measuring.

Inspect the connecting cables and test leads for possible wear, cracks, or breaks before each

use.

For maximum safety, do not touch the test cables or any instruments while power is applied

to the circuit under test. Turn off power and discharge any capacitors before connecting or

disconnecting cables from the instrument.

Section 2 - Safety


Do not touch any object which could provide current path to the common side of the circuit

under test or power line (earth) ground. Always make measurements with dry hands while

standing on a dry, insulated surface capable of withstanding the voltage being measured.

Instrumentation and accessories should not be connected to humans.

WARNING : The instrument should not be opened by anyone other than the manufacturer,

their agent or a competent person, as this may compromise the performance of the instrument

and user safety.

WARNING : If this instrument is used in a manner not specified in this manual, the safety

of the instrument may be compromised.

Section 3 - Introducing The 455 System


4. Introducing The 455 System

4.1 Introduction

This section is intended to enable the new user to quickly and easily learn how to use the

Beran 455 Transducer Calibration System using a simple test method. The tests to be

performed do not require anything more than the Beran 455 system, Getting Started Disk, two

BNC leads and a BNC “T” piece.

4.2 Setting Up The Beran 455 System

Connect the 455 keyboard to the “Keyboard” socket on the rear panel.

Using 2 BNC leads and a BNC ‘T’ connect the generator output and the measurement

channels A ‘V HIGH’ and B ‘V HIGH’ inputs together with the Differential/Single switch set

to ‘Single’ Sided. Other test devices and test equipment are not required for this test

simulation.

Insert the “Getting Started Disk” supplied into the floppy disk drive. The disk contains pre-

programmed configurations allowing the user to quickly learn the basics of the Beran 455

system.

Power the system ensuring the green ‘POWER’ light is illuminated on the front panel above

the ‘TESTING’ ident.

The machine will perform a self test verifying installed components.

The software will load automatically displaying the Transducer Calibration System front page

menu.

4.3 Learning To Test

Using either the front panel keys or the 455 keyboard select the ‘Test’ menu.

The ‘Testing Configuration’ menu will be displayed.

The highlight box displayed can be moved up and down the screen using the [] [] cursor

keys.

4.3.1 Loading Transducer Configuration

To load a pre-configured ‘Transducer’ configuration, position the cursor at the top of the

screen alongside the ‘Transducer’ title field.



Select the ‘List Known Transducers’ softkey. A list of pre-configured transducers will be

displayed. Move the highlight box to select the ‘System Test, Transducer’ configuration.

Press ‘Select’ softkey loading the configuration from disk into the ‘Testing Configuration’

page.

4.3.2 Entering Transducer Serial Number

In the field below the ‘Transducer’ is the ‘Serial Number’ field. Move the highlight box to

this field and enter the serial number ‘Getting Started’.

4.3.3 Loading Reference Transducer

The reference transducer configuration is required to be loaded from disk into the ‘Testing

Configuration’.

Position the cursor bar alongside “Reference” and select ‘List Known References’ softkey. A

list of pre-configured references will be displayed. Move the highlight box to select the

‘System Test, Reference’ configuration. Press the ‘Select’ softkey, loading the configuration

from disk into the ‘Testing Configuration’ page.

4.3.4 Loading Exciter Information

The Exciter configuration is required to be loaded from disk into the ‘Testing Configuration’.

Position the highlighter next to the ‘Exciter’ field and select the ‘List Known Exciter’ softkey.

A list of pre-configured exciters will be displayed. Move the highlight box to select the

‘System Test, Exciter’ configuration. Press ‘Select’ softkey loading the configuration from

disk into the ‘Testing Configuration’ page.

4.3.5 Loading Test Profiles

Before any testing can commence a test profile must be loaded from the floppy disk.

To load a profile highlight the ‘First Profile’ field. Use the ‘List Known Profiles’ key to

display an index of all available profiles.

The first test to be performed is a frequency step. To load the required profile move the

highlight box to select ‘Frequency Step 20Hz to 1kHz @ 1g RMS’ profile. Press the ‘Select’

softkey loading the profile into the ‘Testing Configuration’ page.

The second test is a frequency sweep from 10Hz to 1kHz at 1g RMS. To load the profile in

to the ‘Testing Configuration’ move the highlight box to the ‘Second Profile’ field and again

using the “List Known Profiles” key select the profile ‘Frequency Sweep 10Hz to 1kHz @ 1g

RMS’. Press the ‘Select’ softkey loading the profile into the ‘Testing Configuration’ page.

The third test to be performed is an amplitude step from 0.1g RMS to 10g RMS at 80Hz.

Move the highlight box to the ‘Third Profile’ field and select the test titled ‘Amplitude Step

0.1g to 10g RMS @ 80Hz’ using the same method as selecting the two previous profiles.



4.3.6 Starting The Tests

After loading each profile the system returns to the ‘Testing Configuration’. Position the

highlight box at the ‘Transducer’ field at the top of the page.

To start testing select the ‘Start All Tests’ soft key.

A warning box will be displayed informing the user that the reference is not calibrated for at

least one measurement point and the user is required to press the <Enter> key to continue the

test. This warning message is displayed because the frequency sweep to be performed is not

making measurements at the specific frequencies that the reference transducer was calibrated

at.

Upon pressing <Enter> a message will be displayed stating that the Transducer Calibrator

System is measuring the nominal sensitivity of the test transducer.

The first profile test will begin. The status line displays the current testing frequency of the

instrument in the field ‘Gen Freq:’ . The ‘Analyser State’ changes from ‘Idle’ to ‘Measuring’

at each measuring point.

The display changes showing a bode plot with the x-axis displaying the frequency range for

the test profile. For the first profile the x-axis will display 20Hz to 1kHz, for the second

profile the range will be displayed as 10Hz to 1kHz. The x-axis displays the measured

sensitivity of the transducer. For the tests performed the measured sensitivity will be

500pC/g.

When the first profile has been completed the second profile will immediately start, again

displaying a bode plot of the frequency range against the nominal frequency

The third profile will automatically start. For the amplitude step the X-axis will be scaled into

the amplitude range of the profile, in this case 0g to 10g.

4.3.7 Displaying Test Results

On completion of the tests the display will return to the ‘Testing Configuration’ page. To

draw or tabulate the results of the first test, position the highlighter box on the ‘First Profile’

and select ‘Draw Results’ or Tabulate Results’. Similarly, to draw the second and third

profile results position the cursor on the corresponding field.

4.4 Printing Results

From the results page the user has the option to output the results to a PC format disk

allowing individual test results to be inserted into a word processor or immediate printing to a

PCL5 compatible printer.

Alternatively the results may be printed using the softkey ‘Output All Results’ from the

transducer field. For storing the results to a PC format disk, refer to section 8.5.

Section 4 - Introducing The Transducers Under Test Menu


5. Introducing The Transducer Under Test Menu

5.1 Introduction

This section introduces the new user to the “Transducer Under Test” menu. By following

this section the user should be able to configure a simple fictional transducer.

5.2 A Fictional Transducer

The following fictional transducer specification sheet is based upon a real transducer.

The Fictional Transducer Company

Standard Charge Accelerometer Type 57321 Used for measuring low level vibrations with higher sensitivity

Charge Sensitivity : 31.6pC/ms-2 2% (310pC/g) Mounted resonance frequency : 13kHz

Frequency Range : 0.1Hz to 4kHz (10%) Mounting Thread : 10-32UNF Weight : 175gram (6.16oz)

Temperature Range : -40 to +250C (-40 to +482F) Max. Operational Shock : 500g PK Max. Operational Continuous Sinusoidal Acceleration : 500g PK

Section 4 - Introducing The Transducers Under Test Menu


5.3 Configuring The Transducer

5.3.1 Entering the Transducers Menu

From the Beran 455 Main Menu select the “Transducers” function key. The “Transducer

Under Test” menu will be displayed.

5.3.2 Data To Enter

The user is now required to enter the transducer information.

Set the “Manufacturer” type to “Fictional Transducer Co.”.

Set the “Model Number” to “57321”.

Set the “Measured Parameter” to “Acceleration” and the “Interface” type to “Charge”.

Set the “Input Gain” to “1.000mV/pC”.

Enter “310pC/g” for the “Nominal Sensitivity” , “at” “80Hz 1.0g RMS”.

For “Operational Range” the maximum is “500g PK”. Set the “Mass” of the transducer to

“175” grammes.

Set the “Frequency Range” of the transducer to “0.1Hz to 4000Hz”. The “Warm Up” time

for the transducer to “0 Mins”.

Set the “Temperature Range” to “-40 to +250C”.

Set the “Cal Period” to the required calibration period of the transducer, i.e. “12 months”.

5.4 Storing/Printing Transducer Configuration

Move the highlight box to the “Manufacturer” field and select the “Save Set-up” key to store

the configuration to disk. The “Print Config” will print the configuration to a PC format disk

or printer, whichever the user has selected (refer to section 8.5).

Section 5 - Introducing The Setting Profiles Menu


6. Introducing The Setting Profiles Menu

6.1 Introduction

The Beran 455 system allows the user to make three types of test profile. They are

“Frequency Step”, “Amplitude Step” and “Frequency Sweep”.

6.2 Programming A Frequency Step

In this example, a profile is required making measurements of the test transducer between

20Hz and 1kHz at the same frequencies that the reference transducer has been calibrated at.

The amplitude of vibration is to be a constant 1g RMS. The control parameter is to be

acceleration.

The method used is as follows:

1. Select the “Profiles” softkey from the 455 main menu.

2. Enter a profile “Name”, for example “Frequency Step 20Hz to 1kHz at 1g RMS”.

3. Move the highlight box to the “Profile Type” field, use the function keys to select

“Frequency Step”.

4. Select the “Control Parameter” to be “Acceleration” using the function key.

5. Enter the “Amplitude” value to be “1g RMS” selecting “Imperial Units” and “RMS”

using the relevant function keys.

6. The “Frequencies” are entered using the “Edit Table” function key. Refer to the

calibration frequencies of the reference transducer and enter these frequencies. For this

example the reference transducer has been calibrated at 20, 25,31.5, 40, 63, 80, 125, 160,

200, 315, 400, 500, 630, 800 and 1000Hz.

7. In the amplitude columns enter the value 1g RMS and on completion return to previous

screen using the “Exit” softkey.

8. For the “Frequency Range” enter “20Hz” to “1000Hz”.

6.3 Programming An Amplitude Step

An amplitude step profile is required from 0.1g RMS to 10g RMS at 80Hz, again using

acceleration as the control parameter.

The method is as follows:

1. Select the “Profile” softkey from the 455 main menu.

2. Enter a profile “Name”, for example “Amplitude Step 0.1g RMS to 10g RMS at 80Hz”.

3. Move the highlight box to the “Profile Type” field and use the function keys to select

“Amplitude Step”.

4. Select the “Control Parameter” to be “Acceleration” using the function key.

5. The “Amplitude” profile points are entered via the “Edit Table” softkey. For this test the

amplitudes to be used are 0.1, 0.2, 0.4, 0.6, 0.8, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0 and

10g RMS, all at 80Hz.

Section 5 - Introducing The Setting Profiles Menu


6. The “Frequency” values are to be set to 80Hz and on completion return to the previous

screen using the “Exit” softkey.

7. Enter the “Amplitude Range” values to be “0.1g RMS” to “10g RMS”.

6.4 Frequency Sweep Profile

To program a frequency sweep profile use the same initial methods as above but setting the

“Profile Type” to “Frequency Sweep”.

Set the “Control Parameter” as “Acceleration” with an “Amplitude” of “1g RMS”.

The measurement frequency points are calculated from the frequency range and sweep

increment settings. For this example set the frequency range as 10Hz to 1000Hz with a

“Sweep Increment” of “20 Steps Per Decade”.

The user can check their settings against the “Frequency Sweep 10Hz to 1000Hz @ 1g RMS”

profile stored on the Getting Started disk.

6.5 Saving/Printing Profile Configurations

After a new profile has been created or modified it requires storing to disk. To do this the

highlight box is to be placed on the “Name” field of the “Profile Configuration” menu.

Insert the configuration disk (see 17.5.3) into the floppy disk drive and use the function key

“Save Setup” to store the profile to disk. To print the profile use the “Print Config” key.

The profile will be either printed to a disk file or printed direct to a printer depending on the

user settings.

Section 6 - Introducing The Reference Menu


7. Introducing The Reference Menu

7.1 Introduction

This section introduces the user to the information required to enter the reference transducer

parameters. Although the example reference transducer is fictional, it has been based upon an

actual reference transducer.

7.2 Information Required

The manufacturers data sheet for the type of reference transducer used and the specific

calibration results at each frequency are required.

Figure 1 shows the Fictional Manufacturers Data Sheet.

The Fictional Transducer Company

Reference Accelerometer Model No: 9871 Industrial standard reference transducer used for calibration of accelerometers and velocity transducers. Specification Charge Sensitivity : 10pC-pk/g-pk (nominal) Resonant Frequency : Greater than 25kHz

Frequency Response : 10pC/g 5% 10Hz to 10kHz Dynamic Range : 0.01g to 100g

Amplitude Linearity : 2% Shock Limit : 7000g (10ms)

Temperature Range : -75C to +250C Acoustic Response : 50Hz to 50kHz less than 0.1g RMS Magnetic Field Response : Less than 0.001g RMS/100 gauss 50-60Hz

Humidity Effects : 100%RH 20-100 (non-condensing) No effect

Insulation Resistance : -75C to 75C Greater than 10,000M Maximum Mass Of Test Transducers: 400 grams Weight : 450 grams Material : Titanium



Figure 1 Fictional Reference Transducer Specification

The fictional reference transducer calibration results are shown in figure 2.

The reference transducer Serial Number B1234 was calibrated to NAMAS standards using a computer system, two NAMAS calibrated digital voltmeters, frequency counter and a reference transducer meeting the Physikalisch-Technische Bundesanstalt, Braunschweig specification. The computer system recorded the results from the transducers at each of the discrete measurement frequencies.

The calibrations were carried out with an ambient temperature of 20C 2C with a relative humidity <60%. The nominal acceleration was in the range of 15 to 55ms-2 peak depending on frequency. To compare these results and the results given in pC/g it should be noted that 1g=9.80665ms-2.

Accelerometer capacitance 986pF 0.5% Leakage resistance > 100 M 5% Date of calibration 18th December 1997.

Frequency

Hz

Sensitivity

pC/ms-2

Frequency Hz

Sensitivity pC/ms-2

20 0.892 1,000 0.866 25 0.892 1,250 0.864 31.5 0.890 1,600 0.862 40 0.889 2,000 0.859 63 0.885 2,500 0.858

Nominal Sensitivity 80 0.884 3,150 0.857

125 0.881 160 0.880 200 0.878 315 0.874 400 0.872 500 0.871 630 0.869 800 0.867

Accelerometer capacitance 986pF 0.5% Leakage resistance > 100 M 5%



Figure 2 Fictional Reference Transducer Calibration Results

7.3 Data To Be Loaded

Select the “Reference” softkey from the Beran 455 main menu.

Enter the manufacturers name, transducer model number and transducer serial number in the

relevant fields. In this case the manufacturer is “Fictional Transducer Co”, the model

number is “9871” and the serial number from the calibration results sheet is B1234.

The “Measured Parameter” is set using the softkeys to “Acceleration” and the “Interface”

type set to “Charge”.

The “Input Gain” field requires to be set to 1mV/pC.

The “Nominal Sensitivity” value to be entered is measured at 80Hz. From the calibration

results the value to be entered is 0.884pC/m/s/s at a vibration level of 15m/s/s pk.

With the highlight bar set on the “Nominal Sensitivity” field the user has the option to enter

all calibration frequency points of the reference transducer. This reference table is accessed

via the “Edit Table” soft key. In the reference table the user enters the specific calibration

frequencies, the amplitude range of calibration (15-55m/s/s as per the calibration results), the

sensitivity in pC/m/s/s and the phase. In this example the phase has not been calibrated by

the calibration laboratory, therefore the phase value has been set to 0.0.

The “Operational Range” of the transducer is the dynamic acceleration range of the

transducer. In this example the maximum value of the dynamic range is 100g RMS

(980m/s/s RMS). The mass range the reference transducer results are valid over is entered in

the “Payload” field. In this case 400 grams.

The “Frequency Range” values are 10Hz to 10000Hz read directly from the manufacturers

specification.

The “Temperature Range” for the 9871 is stated as -75C to +250C and is entered directly

into the these fields.

The “Last Calibrated” is the date the reference was last calibrated, indicated on the

calibration results as the “18th December 1997” which should be as “18-12-97”. Finally the

“Cal Period” is the time span to the next calibration of the reference transducer, typically set

to 12 months.

7.4 How The Settings Should Look

Figure 3 shows the reference data entered for this fictional reference transducer.



7.5 Saving/Printing Reference Transducer Information

Insert the “Configuration Disk” into the floppy disk drive.

Beran Instruments 455 Transducer Calibration System 14 Jan 1998 Page 1

Manufacturer Fictional Transducer Co

Model Number 9871

Serial Number B1234

Transducer Info

Measured Parameter Acceleration

Interface Charge

Sensitivity 0.884 pC/m/s/s at 80.000 Hz 15.000 m/s/s RMS

Operational Range 980.665 m/s/s RMS

Payload 0.000 gm to 400.000 gm

Frequency Range 10.000 Hz to 10000.000 Hz

Temp Range -75.000 Deg C to 250.000 Deg C

Calibration Period 12 Months

Last Calibrated 18 Dec 2000

Number Of Calibration Points 20

Frequency Amplitude Sensitivity Phase

Hz m/s/s RMS pC/m/s/s Degrees

20.000 15.00-55.00 0.892 0.000

25.000 15.00-55.00 0.892 0.000

31.500 15.00-55.00 0.890 0.000

40.000 15.00-55.00 0.889 0.000

63.000 15.00-55.00 0.885 0.000

80.000 15.00-55.00 0.884 0.000

125.000 15.00-55.00 0.881 0.000

160.000 15.00-55.00 0.880 0.000

200.000 15.00-55.00 0.878 0.000

315.000 15.00-55.00 0.874 0.000

400.000 15.00-55.00 0.872 0.000

500.000 15.00-55.00 0.871 0.000

630.000 15.00-55.00 0.869 0.000

800.000 15.00-55.00 0.867 0.000

1000.000 15.00-55.00 0.866 0.000

1250.000 15.00-55.00 0.864 0.000

1600.000 15.00-55.00 0.862 0.000

2000.000 15.00-55.00 0.859 0.000

2500.000 15.00-55.00 0.858 0.000

3150.000 15.00-55.00 0.857 0.000

Figure 3 The Reference Parameters Entered



Move the highlight bar to the “Manufacturer” field. Use the function key “Save Setup”.

The “Print Setup” key produces a hardcopy of the reference transducer settings (refer to

section 8.5).

The reference information may now be used in the test configuration page.

Section 7 - Introducing The Utilities Menu


8. Introducing The Utilities Menu

This section introduces the new user to the contents of the Utilities menu.

8.1 Entering The Utilities Menu

Select the “Utilities” soft key from the 455 main menu. A further utilities sub-menu is

displayed giving access to “Config Exciter”, “Config Hardware”, “Config System”, “Save

Setup” and “Additional Utilities” menus. Selecting any of the soft keys will select the

appropriate sub-menu.

8.2 Configure Exciter Sub-Menu

The exciter (shaker) operational parameters are entered on this page. When running test

profiles the exciter configuration is checked to ensure that damage will not occur.

Under “Exciter” enter the manufacturers name and model number in this field.

Under “Frequency Range” enter the operational frequency of the exciter.

The “Maximum Acceleration”, “Maximum Velocity” and “Maximum Displacement” values

are directly read from the manufacturers data sheet.

Enabling “Soft Ramping” protects the shaker from producing a large displacement at lower

frequencies by increasing the amplitude at a lower rate.

8.3 Example Shaker

The following example is a fictional shaker.

The Fictional Shaker Manufacturer

Model Number F239B Sinusodial Force Peak Newtons (pounds) 100 (22.5) Maximum Acceleration Peak m/sec-2 (g) 588 (60) Max. Velocity Peak m/sec (in/sec) 1.52 (60) Moving Mass Kg (lbs) 0.17 (0.35) Max. Displacement pk-pk mm (in) 10.0 (0.4) Displacement to stops mm (in) 10.8 (0.425) 1st Major resonance nom Hz 12000 Frequency Range Hz 1-14000 Suspension Stiffness axial Kgf/mm (lbf/in) 1.14 (64) Cooling Natural Magnetic Field Permanent Magnet



The above data has been loaded into the exciter configuration page producing the

configuration below:

Beran Instruments 455 Transducer Calibration System 15 Jan 1998 Page 1

Exciter Fictional Shakers Manu, F293B

Test Due Not Req'd

Frequency Range 1.000 Hz to 14000.000 Hz

Max. Acceleration 588.000 m/s/s Peak

Max. Velocity 1520.000 mm/s Peak

Max. Displacement 10000.000 um pk/pk



Note that the velocity is specified as 1.52m/sec and is entered as 1520 mm/s in the Beran 455.

Displacement is entered as micro-meters and therefore the user is required to convert the

specified mm to m, in this case 10000m. The engineering units are also very important as

pk-pk is approximately 2.8 times larger than RMS values and therefore could result in serious

damage to the shaker.

8.4 External Test Hardware

The user is able to enter details of any external signal conditioning instrumentation used as

part of the ‘Automatic Calibration System’. For example, if external signal conditioning

amplifiers form part of the calibration system, information such as their serial numbers and

calibration dates may be entered. This information will then be outputted when a hard copy of

calibration results is made.

8.5 Configure System

The configure system menu enables the user to configure system settings. The most

commonly used sections of the configure menu are discussed in this section.

“Settling Time” is the time taken for the system to stabilise prior to making a measurement.

Entered as “Seconds” and “Cycles”.

“Measurement Time” is the integration time taken for each measurement and is entered as

“seconds”or “cycles”.

“Text Output” allows the selection between serial, parallel and PC format disk output types

for the output of text result information. The format is selectable between either PCL-5,

ASCII for Spreadsheet and ASCII types.

“Graph Output” allows the selection between serial, parallel and PC format disk outputs

types for the output of graphical result information. The format is selectable between PCL-5

and HPGL protocols.

For hardcopies of system configurations the user can select between printer output or an

output to a PC format disk. This enables the user to export the configurations to a word

processor.

8.6 Save Setup

The user is given the option to store the current system configuration setup either internally or

to the configuration disk. The system will automatically recall the setup upon power up, this

recall will be from disk if the configuration disk is present in the drive, or from memory if the

disk is not present.

8.7 Additional Utilities



The access codes are entered in this section by the configuration manager. Other options

available are to “Format Data Disk”, “Format Config Disk” and make a “Master Disk

Copy” storing all profiles and configurations to disk. The IEEE address of the system is also

entered on this page.

Section 8 - Installation And Operating Controls


9. Installation And Operating Controls

This section contains information and instructions for unpacking and installing the Beran 455

Vibration Transducer Calibrator. It also introduces the layout of controls on the instrument.

9.1 Unpacking and Inspection

Every care is taken in the choice of packaging material to ensure that your equipment will

reach you in perfect condition.

If the equipment has been subjected to excessive handling during transit, evidence of this is

likely to be visible on the shipping material.

In the event of damage, the shipping container and cushioning material should be kept for the

carrier’s inspection.

Unpack the equipment and inspect for external damage to the case, sockets, keys etc. If

damage is found, please notify the carrier and your sales representative immediately.

Standard accessories supplied with the instrument are listed in Section 2.6.

9.2 Introducing The Front Panel

The 455 front panel contains an integral electro-luminescent display, which allows the

responses of the transducer under test to be viewed and forms the main user interface.

The front panel incorporates soft touch keys allowing the user to move between menus and

enter information into the system. The “Abort” key is an emergency stop button removing

the signal generator and shaker outputs immediately. The “Step”, “Run” and “Pause” keys

can be used during a test profile whilst it is running allowing the user to interrupt the test.

The numeric keypad allows information to be entered whilst the cursor keys move the

highlight box through the menu structure.

The front panel also incorporates integral ‘secret till lit’ display LED’s which show when

power is present at the unit, when the generator output is switched on and when the inputs to

the internal signal conditioning amplifiers are at an over-range condition.

The over-range indicators will become illuminated when the output from the internal signal

conditioning amplifiers, into the measurement circuitry exceeds 10V pk. This takes into

account the currently selected input type and input gain setting for the specified measurement

channel. For example, an over-range condition will occur when a charge input type is selected

with an input gain of x10 if the input level exceeds 1000pC pk (assuming the 1mV/pC

transfer function).

9.3 QWERTY Keyboard



A PC compatible QWERTY Keyboard is supplied with the 455 system which plugs into the

KEYBOARD port on the rear of the instrument.

The function keys F1 - F6 on the QWERTY keyboard duplicate those on the instrument front

panel allowing the 455 to be controlled from either.

9.4 “Undo” Function

When entering text information into the system, the function key F1 has the identifier

“Undo”. Pressing this key replaces the made with the previous text.

9.5 “Help” Function

By pressing the ‘HELP’ key on the QWERTY Keyboard or the ‘HELP’ key on the instrument

front panel the operator may request information regarding the current configuration

parameter. The current parameter is the field where the highlight cursor is currently

positioned.

9.6 Status Line

Regardless of the current display, a status line is always displayed at the top of the instrument

screen. This informs the operator as to the current generator frequency and the state of the

analysers (Idle or Measuring).

9.7 Principle of Operation

The signal generator of the 455 drives the calibration shaker via the internal power amplifier.

The reference and test transducer, mounted back-to-back on the calibration shaker generate

signals proportional to the vibration amplitude being received from the shaker. These signals

are scaled and amplified by the internal precision amplifiers, which convert the input signals

from the transducers to a scaled voltage output. This output is fed both to the system analyser

channels and to the monitor output connectors on the rear of the unit, which allow external

measurements to be made in parallel with the 455 analyser channels if required. The

maximum output level allowed form the input amplifiers is 10V pk, after the application of

any input gain and selection of the required conversion type. For example, an over-range

condition will occur when a charge input type is selected with an input gain of x10 if the

input level exceeds 1000pC pk (assuming the 1mV/pC transfer function). A high level

schematic of the system may be seen in figure 4.



A constant input drive amplitude to the calibration shaker is maintained by the signal

generator, power amplifier, calibration shaker, reference transducer and reference analyser

channel operating in a closed loop mode. This means that the measured value on the

reference analyser channel is used to control the amplitude level of the 455 signal generator.

The 455 analyser channels use the Single Sine Correlation measurement technique. The

analysers operate effectively as very narrow digital band-pass filters with the centre frequency

always being that of the current generator frequency. The incoming signals from the

transducers (via the precision amplifiers) contain the generator fundamental frequency,

harmonics generated by the calibration shaker and a degree of wide-band noise introduced by

the surrounding environment.

The Single Sine Correlation technique rejects the harmonics and wide-band noise from the

signal, only measuring the fundamental component of the complex signal. The instruments

inherent ability to do this may be enhanced by increasing the ‘Measurement Time’ over which

individual measurements are made. See section 16.3.2.



9.8 System Configurations

Example system configurations are detailed in figure 5.

Figure 5a, Single Sided Voltage Output Reference and Test Transducer

Figure 5b, Single Sided Charge Output Reference Transducer and Differential Voltage Test Transducer

Figure 5c, Charge Output Reference Transducer and Single Sided Voltage Output Test Transducer.



Figure 5d, Charge output Reference Transducer and ICP Type Test Transducer

Figure 5e, Charge output Reference Transducer and Current Output Test Transducer

Section 9 - Hardware And Connection Details


10. Hardware And Connection Details

10.1 Mains Power Supply

10.1.1 Supply Voltage

The instrument can be operated over the voltage range 90 - 225 VAC at a frequency of 47-

63Hz and is automatically selected. The instrument is rated at 3 Amp.

10.1.2 Supply Power Cord

The instrument is supplied with a 3 wire power cord which includes a protective earth

conductor.

WARNING: When using the instrument, the protective earth conductor must be connected

to a safe earth ground at all times.

10.1.3 Inlet Fuse

The inlet fuse is an integral part of the mains power inlet.

To replace the fuse, disconnect the power cord, remove the lid from fuse compartment with a

small screwdriver, remove blown fuse and replace with a 3 Amp, 20mm (T) fuse.

WARNING : Disconnect power cord before opening fuse compartment.

CAUTION : Only use correct rating of fuse or the instrument could become damaged.

10.2 Cleaning

The instrument can be cleaned using a soft cloth.

If this fails to clean the instrument, a damp cloth with a mild detergent may be used or a non-

abrasive foam cleaner.

WARNING : Disconnect power cord before cleaning unit.

10.3 Cooling

The instrument is cooled by two exhaust fans on the rear panel.

CAUTION : Should the either of the exhaust fans become blocked or fail, the performance

of the instrument could be affected, in this case the instrument should be returned to the

vendor servicing.



10.4 455 Rear Panel Connectors

The following connectors are available at the rear of the instrument:

Mains Inlet:

Allows a power supply connection to the unit to be made.

Generator Output:

Output from the internal signal generator, allowing the use of an external power

amplifier to drive the calibration shaker if necessary.

Shaker Power Output:

Output from the internal power amplifier for connection to the calibration exciter.

Inputs (Q):

Allows direct connection of charge output type transducers to either the Channel A or

Channel B input analyser channels. Full input range is 10,000pC pk (with an input gain

of x1).

Input (I):

Allows direct connection of ICP type current transducers to either the Channel A or

Channel B input analyser channels. ICP compliance is 30V @ 4.7mA.Full input range

is 10,000mV pk (with an input gain of x1).

Voltage (V):

Allows direct connection of either single ended or differential voltage output type

transducers to either the Channel A or Channel B input analyser channels.

Differential/Single Ended operation is achievable via a switch on the rear panel. Full

input range is 10,000mV pk (with an input gain of x1).

Serial (RS232):

Allows connection of pen plotters for graphical output or a connection to a PC system

for either direct results output or for operation with the Beran 485 Transcal application.

Parallel:

Allows connection of PCL-5 or HPGL compatible output devices for creation of

hardcopy results.

IEEE-488:

Allows operation of the instrument to take place over a GPIB interface.

Keyboard:

Allows connection of a PC compatible PS2 style keyboard.



10.5 Optional Rack Mounting

Optional Rack Mounting flanges can be provided, to enable the instrument to be fitted into a

standard 19” rack. To replace the factory fitted handles remove the top and bottom securing

screws. Fit rack mount flanges and refit the securing screws.

Section 10 – Powering On And Powering Off


11. Powering On And Powering Off The 455 Instrument

See paragraphs 10.1 to 10.1.3 for relevant connection details for the 455 units power supply.

11.1 Powering On

Before turning on the instrument, ensure that no external equipment is connected which could

be damaged.

The power switch for the instrument is on the rear panel of the unit, integral with the power

inlet connector. When the unit is turned on, a sequence of internal self tests are performed.

These take a short time to complete, during which the internal components stabilise to their

nominal operating tolerances.

At the completion of the self test procedure, the main system menu will appear on the screen.

From here, complete system functionality may be controlled.

11.2 Status Line

Across the top of the screen a status line is displayed. This gives information about the

current state of the instrument, and is visible at all times. The information given here is as

follows:

Current Generator Frequency

State of Instrument (Idle, Measuring)

Sweep Status (Up/Off)

11.3 Powering Off The 455 Instrument

To power down the Transducer Calibration System the user is advised to follow the

procedure below:

1. If required store the entire system configuration, either to internal memory or floppy

disk refer to section 17.4.

2. Switch off the power to the instrument using the rear panel mounted mains switch.

Section 11 - Using The Menus


12. Using The Menus

The 455 analyser is based around a comprehensive menu system, to allow the user to quickly

become familiar with its operation. There are five main menu groups, together with several

sub-menus.

12.1 Finding the Correct Menu

The menus are arranged in a layered format, with the main menu, at the top. From the main

menu, the five most commonly used menu screens are available. To enter one of these five

menus, simply press the appropriate softkey from the main menu:-

To leave a menu, press the extreme left hand softkey labelled “Exit”, which will return you to

the previous menu.

The main functions of the five basic menus are explained in the next few pages.

12.1.1 Testing Menu

This menu allows the user to select the transducer under test, reference transducer, exciter and

test profiles from pre-configured lists. Additionally, supplementary information such as the

operators name and current operating conditions (temperature, humidity etc..) may be entered.

12.1.2 Transducers Menu

This menu allows the user to configure each new test transducer type.

12.1.3 Profiles Menu

This menu allows the user to configure each test profile, setting frequency and amplitude

steps as well as frequency sweeps.

12.1.4 Reference Menu

This menu allows the user to configure each reference transducer.

12.1.5 Utilities

Allows the user to configure optional system parameters, detailing the external test

equipment, exciter safety limits and password access levels. The user is able to set the results

output device as either a parallel or serial interface printer for a hardcopy result or as an

output to disk.

Leave System

Test Transducers Profiles Utilities References



12.2 Selecting Menu Options

Once the required menu screen has been reached, the up, down, left and right cursor keys may

be used to position the highlighted block over the option that is to be changed or set. Once

the block is in the correct position, the new value may be entered, using either the numeric

keypad, softkeys or QWERTY keyboard.

12.2.1 Entering Numeric Information

Numeric information may be entered using either the front panel or the QWERTY keyboard.

As the keys are pressed, the value displayed inside the highlighted block will update, to show

the new setting.

The delete key may be used to rub out the last character entered. The ‘Undo’ key (F1) may be

used in order to regain the previous entry.

12.3 Connecting the 455 Controller

The 455 Controller is connected to the other system components as follows:

Input Channel A:

This would usually be connected directly to the ‘Reference Transducer’. The reference

transducer configuration within the 455 application will then be used to automatically set the

input type and any input gain when the reference transducer is selected for use.

CAUTION: It is important that test programs are not run if the connection from the

Reference transducer to the 455 Input Channel is not complete. This is due to

the closed loop being broken that will cause the generator output to

progressively increase, which may damage the shaker mechanism.

Input Channel B:

This would usually be connected directly to the ‘Transducer Under Test’. The transducer

configuration within the 455 application will then be used to automatically set the input type

and any input gain when the transducer type is selected for calibration.

It is recommended that the manufacturers handbook for any other devices which are to be

connected to the Beran 455 system are read and understood before connection to the system is

made.



Shaker:

The calibration shaker is connected directly to the system via this connection. The internal

power amplifier is rated at 150Watts and is suitable for the connection of any small shaker

system. An internal cut-out circuit is employed to provide protection should the output of the

power amplifier rise above 5.5A. If this occurs, the power supply to the power amplifier will

be isolated and will not be re-instated until the manual ‘RESET’ button on the rear of the unit

is depressed. If the power to the amplifier is cut off in this way, the red ‘TRIP’ LED on the

rear of the unit will also become illuminated. Additional protection is also offered through the

use of a 5A quick blow fuse, wired in series with the shaker output.

If the power amplifier trip continues to operate during a test, the test profile should be

modified in order to reduce the output loading effect of the shaker. This may normally be

achieved by either increasing the test frequency or by reducing the displacement of the test

profile. If this is not possible, an external power amplifier may be employed, driven by the

signal output available at the ‘Generator’ connection point of the rear of the unit.

12.4 Restarting the Transducer Application

Note: This menu option will not power down the instrument. To power down the instrument

refer to section 11.3.

The “Leave System” function key enables the user to reboot the instrument and load a

different system configuration from either the systems internal configuration memory or an

alternate configuration disk. The loaded configuration will contain another set of stored test

transducers, reference transducers and profiles settings. The user is required to insert the

appropriate configuration disk into the disk drive before the system is re-booted.

If the user has stored a system configuration to the disk then this will be recalled into the

instruments operating memory.

Prior to rebooting the system the user is given the option to store the current system

configuration to internal memory or to the currently inserted configuration disk, using the

softkeys “Save Internally” or “Save To Disk” respectively.

The user is advised to follow the procedure given below to load a different configuration from

a configuration disk into the system operating memory:-

1. Press the “Leave System” softkey.

2. The user is given the option to store the configuration to either the internal memory

or to a configuration disk, using the appropriate softkeys. To skip storage of the

system configuration press “ENTER”.

3. The leave calibration system message is displayed, the user is again given the option

to skip re-booting the system by pressing “ENTER” or to reboot the system by

pressing the “Confirm” softkey.

4. Insert the appropriate configuration disk into the floppy disk drive press the

“Confirm” softkey.

5. The system will reboot and perform the power-up self-tests prior to redisplaying the

transducer calibration system main menu.



The user is advised to follow the procedure given below to load the configuration from

internal memory:-

1. Press the “Leave System” softkey.

2. The user is given the option to store the configuration to either the internal memory

or to a configuration disk, using the appropriate softkeys. To skip storage of the

system configuration press “ENTER”.

3. The leave calibration system message is displayed, the user is again given the option

to skip re-booting the system by pressing “ENTER” or to reboot the system by

pressing the “Confirm” softkey.

4. Remove any floppy disks from the disk drive and press the “Confirm” softkey.

5. The system will reboot and perform the power-up self-tests prior to redisplaying the

transducer calibration system main menu.

Section 12 - Test Menu


13. Test Menu

To carry out the calibration of a transducer the “Test” menu must be entered. This is achieved

by selecting the “Test” softkey on either the instrument front panel or “F2” on the keyboard.

The “Testing Configuration” menu page is then presented which allows the details of the test

and reference transducers to be entered as well as the selection of the required test profiles.

13.1 Transducer

The transducer type under test is selected from the list of available of pre-configured

transducers on the configuration disk. This is achieved by selecting the “List Known

Transducers” softkey. To select the required transducer, position the highlight box over the

transducer and press the “Select” key.

The available test transducer details are then recalled from the configuration disk. If a new

transducer configuration is required, refer to section 13 of this manual.

The Transducer field also allows the option of starting all tests or outputting the results of all

previous tests using the appropriate softkey.

13.2 Serial Number

After selection of the test transducer type, the device serial number is to be entered. The

default title “Serial Number” may be modified via the softkey labelled “Change Identifier”.

This allows an alternative field name such as asset number to be used.

All information including the identifier string will appear on all hardcopy results.

If test results are stored to a PC format disk (see 17.3.13) this unique number is also used to

identify the filename. It is advisable that the entered information consists of eight characters

or less when storing results in this format.

13.3 Transducer Information

A single line of information is displayed to direct the operator to note or perform a certain

task. For example, “See test spec 4238 Issue 3” or “Use Isolating Mounting Plate”.

The actual text displayed is entered (via password access) from the “Transducer” menu option

(see 14.7).

13.4 Reference

The reference transducer is selected from the list of available pre-configured references on the

configuration disk. This is achieved by depressing the “List Known Reference” softkey. A

list of configured reference transducers is displayed with the relevant type being selected by

positioning the screen cursor on the relevant transducer and depressing the “Select” softkey.



The reference transducer details are then recalled from the configuration disk. If the required

reference transducer details have not already been entered into the system, this is achieved

(via password access) with the “References” option from the main menu (refer to section 15).

13.5 Exciter

The exciter (shaker) to be used for calibration is selected from the list of available pre-

configured exciters on the configuration disk. This is achieved by depressing the “List

Known Exciters” softkey. A list of exciters known to the system is displayed with the

relevant type being selected by positioning the screen cursor using the up and down cursor

keys and depressing the “Select” softkey.

The exciter details are then recalled from the configuration disk. If the required exciter

details have not already been entered into the system, this is achieved (via password access)

with the “Exciter” option from within the “Utility” menu (refer to section 16).

13.6 Operator

The operator is able to enter their name and the ambient conditions of temperature, pressure

and humidity. These details are output to the hardcopy lead sheet with the test results.

Modification of these field titles is carried out by depressing the “Change Settings” softkey

when the “Current Operating Conditions” menu page is displayed.

13.6.1 Operator Name

Up to 40 characters may be entered via the QWERTY keyboard.

13.6.2 Temperature

Up to 15 characters may be used allowing a nominal value and a ± tolerance to be entered. In

addition the System Manager may choose to change the Temperature identifier to an

alternative if required, by depressing the “Change Identifier” softkey.

Entered information will be printed with all results when a hardcopy is produced.

13.6.3 Humidity


addition the System Manager may choose to change the Humidity identifier to an alternative

if required, by depressing the “Change Identifier” softkey.




13.6.4 Air Pressure


addition the System Manager may choose to change the Air Pressure identifier to an

alternative if required, by depressing the “Change Identifier” softkey.


13.6.5 Phase Measurement

The phase difference between the reference and test transducer is measured by the 455 system

and by using the softkeys, phase information may be displayed in either ±180 or 0-360

degree conventions. Alternatively the “Off” softkey suppresses all phase information from

the display screens and hardcopy results.

Phase information is not available during the real-time display of results. Once a test profile

has run, amplitude and phase (if enabled) information may be simultaneously displayed using

the “Draw Results” or “Tabulate Results” softkey.

13.6.6 Display From (Max. and Min Phase Angle Ranges)

The Minimum and Maximum values for the phase axis, displayed when drawing result plots

may be specified when highlighting this option. The “Default” softkey allows the full range

to be reset, (i.e. -180 to +180, or 0 to 360 degrees).

13.6.7 Graph y-axis

Two types of parameter may be selected for the test results graph y-axis. These are the

percentage or dB deviation ranges, the limits of which can be specified by the user. The

measured or stated nominal sensitivity of the transducer (see 13.6.8) is the centre of the y-

axis, i.e. at 0% or 0dB.

If ‘dB’ output is selected and the phase output disabled, the deviation from either the

measured or manufacturers stated sensitivity (see 12.6.8)is also displayed on the tabular

output results.

The percentage deviation ranges may either be displayed on the left or right hand axis of the

graph by selecting the appropriate softkey, e.g. “% on Right Axis” or “% or Left Axis”.

13.6.8 Graph Zero At

The zero sensitivity position on test result graphs may be defined as either the transducers

stated nominal sensitivity, or the actual measured sensitivity during dynamic testing. This

option is set by selecting the appropriate softkey, e.g. “Nominal Sensitivity” or “Measured

Sensitivity”.



13.6.9 Input Gain

The 455 system incorporates internal signal conditioning amplifiers that may automatically

apply a gain of either x1, x10, or x100 for different types of reference and test transducer. If

this is the case, the gain setting to be used will be set in the ‘Transducers’ and ‘References’

configuration pages and further configuration here is not allowed. However, if these

transducer specific gain settings are set to ‘Manual’, the gain entered here will be used

throughout the test.

It is however possible to enter any value of gain in order to compensate for additional external

signal conditioning amplifiers (e.g. enter a gain of 2.0). If this is the case, the gain on the

internal signal conditioning amplifiers will be set to x1, effectively being turned off.

This setting is duplicated in the ‘External Hardware’ page from the ‘Utilities’ menu.

13.6.10 High Pass Filter

The internal signal conditioning amplifiers within the 455 system allow the application of a

5Hz HP filter for either the reference or transducer channels. If this option is required the two

“Enable” and “Disable” softkeys may be used to achieve this.

This setting is duplicated in the ‘External Hardware’ page from the ‘Utilities’ menu.

13.6.11 Access Mode

Three password controlled access modes are provided to ensure system security. The access

modes and level of facilities provided for each are:

Operational Mode 1 - Allows testing and hardcopy to be carried out. No changes to

transducers, references, profiles or hardware configurations are allowed.

Operational Mode 2 - Allows access to the External Gain setting (see 13.6.9) in addition to

the items accessible from Operational Mode 1.

Configurations - All facilities are accessible including the setting of the passwords.

To change from one access level to another requires the relevant password to be entered in the

“Current Operating Conditions” menu page. The password is entered (appearing on the

screen as a series of dashes) with “Enter” depressed on completion. If the password is

correct, the new access level is displayed.

NOTE : that the password is case and space sensitive, i.e. if a password is set to “Level1”

then “level1” will not be accepted.

Passwords may be modified from the ‘Additional Utilities’ page is the ‘Utilities’ section. (see

section 16.5.1)

13.7 Test Profiles



Individual Test Profiles are selected by positioning the cursor bar on the ‘first’, ‘second’,

‘third’ and ‘fourth’ profile fields. The “List Known Profiles” softkey will then display the

pre-configured test profiles on the current configuration disk.

Any test profile may be selected by positioning the cursor bar using the up and down cursor

keys. Depressing the Select softkey will retrieve the test profile from the disk.

13.8 Running A Test Profile

Having retrieved a test profile from the configuration disk it may be run by positioning the

highlight box over it and depressing the “Start Test” softkey. Alternatively, all selected test

profiles may be run by positioning the cursor bar over the “Transducer” field and depressing

the “Start All Tests” softkey.

The test may now be started by depressing the “Run” or the “Step” key on the front panel. In

the latter case the test will pause after each completed measurement. Testing may be resumed

by depressing either the “Step” or “Run” key on the front panel or the “Continue Testing”

softkey.

During the execution of a test profile the nominal sensitivity is measured first, followed by

the individual measurements specified in the selected test profiles. The amplitude results are

presented in real-time in a graphic format. Testing may be aborted at any time during a test

by depressing the “Abort Testing” softkey or “Abort” on the 455 front panel.

13.9 Completion of Testing

On completion of a test profile, the results may be viewed on-screen in either a text or graphic

format by depressing the “Tabulate Results” or “Draw Results” softkeys that become

available when the individual tests are highlighted.

On completion of a set of results, the system can optionally prompt the user to produce a

hardcopy (see section 17.3.15).

If phase information is selected for display (see 6.3.5) the test transducer phase response

relative to the reference transducer is graphically displayed simultaneously with the amplitude

information.

13.10 Hardcopy

Hardcopy’s of test results in either text or graphic format may be obtained upon completion

of testing. First, display on-screen the results by depressing the “Draw Results” or “Tabulate

Results” softkeys.

Hardcopy’s of text results are then obtained by depressing the “Print Results” softkey and

graphic hardcopy by depressing the “Plot Results” softkey.



Alternatively, hardcopy’s of all results from a sequence of tests may be obtained by

positioning the highlight bar over the “Transducer” field and depressing the “Output All

Results” softkey. The “Output All Results” softkey also provides a “lead sheet” detailing

information such as the equipment used, ambient calibration conditions etc.

13.11 Error Messages

A comprehensive range of safety interlocks is provided within the application software to

ensure that no system component is subjected to excess amplitude or frequency levels.

This operates by comparing the maximum and minimum frequency and amplitude levels

specified in a selected test profile with those defined for the reference and test transducers and

calibration shaker. If a test profile selected which contains levels that would exceed the

specified limits for these system components the user is prevented from running the test

profile. An error message is displayed, indicating the system component and parameter that

would have been exceeded had the test profile run. An example error message is:

Depressing “Enter” returns the user to the “Testing Configuration” page to allow the

selection of a different test profile.

An alternative error message is displayed if the selected test profile contains

amplitude/frequency test points where calibration values do not exist for the selected

reference transducer. Normally, to ensure traceability it is recommended that tests on the

transducer under test are only at the specified amplitude and frequency combinations that the

reference transducer was tested at. This then ensures a traceability path from the reference

device. A typical message is:

The user may elect to continue and run the test profile by depressing the “Enter” key. The

test profile will run with the text screen and hardcopy results being annotated:

* Results which are Not Traceable - Reference Not Calibrated at These Points

An asterisk will appear alongside the individual results where traceability is not guaranteed.

* * * Error * * *

Profile: Frequency Step 5Hz - 500Hz

Frequency Outside Allowable Range for Transducer

10Hz

Press Enter To Continue

* * * Warning * * *

The Reference is not Calibrated For At Least

One Measurement Point

30.000Hz 1.000g

Press ENTER to Continue With Calibration, Abort to Stop

Section 13 - The Transducers Menu


14. Transducers Menu

The “Transducers Menu” is used to enter details of each transducer type to be tested. This

information is used to define the conditions under which the nominal sensitivity measurement

for this transducer should be made. Access to this menu is only permitted when in

“Configurations” password mode (see 13.6.11).

The “Transducers Menu” is entered by depressing the “Transducers” softkey from the main

menu. With the cursor bar positioned on the “Manufacturer” line, five softkey choices are

presented.

14.1 List Known Transducers

By depressing this softkey, a directory of the transducers whose details have been previously

entered are recalled from the 455 configuration disk. These are displayed in alphabetical

order and may be recalled by positioning the cursor bar over the required transducer and

depressing the “Select” softkey.

The recalled transducer details may be edited if required and re-saved by depressing the

“Exit” softkey where a screen prompt will request the user to choose between saving the new

details or leaving the previous details unchanged.

14.2 Make New Transducer

By depressing this softkey the transducer details entries are cleared. Completely new

transducer details may then be entered with saving to disk performed in a similar manner to

that in 14.1.

14.3 Erase Transducer

When a transducer has been selected using the method described in 14.1 the details may be

deleted using the softkey. A confirmation is requested by the software prior to the deletion

taking place.

14.4 Save Setup

A selected Transducer configuration may be saved to disk by depressing this softkey.

14.5 Print Config

A text hardcopy of the selected transducer details may be obtained, with the output being sent

to the text device selected (see 17.3.9).

In the event of selecting “Make New Transducer” or to change an existing manufacturer

name, up to 40 alpha-numeric characters may be entered with the cursor bar positioned at the

“Manufacturer” line.



14.6 Manufacturer/Model Number

With the cursor bar positioned at the “Manufacturer/Model Number” line the specific device

details may be entered. For example, Endevco and 2222C.

14.7 Transducer Information

Up to 40 characters may be entered which appears as a screen instruction to the operator

when this specific type of transducer is selected for test. Examples of use are “See Test Spec

4322 Issue 3” or “Use Isolating Mounting Plate”.

14.8 Measured Parameter

The parameter to which the transducer is sensitive is entered by depressing the

“Acceleration”, “Velocity” or “Displacement” softkey. This selection ensures units are in

the correct format i.e. g for acceleration or mm/s for velocity.

The parameter entered here will also determine which of the input types is selected on the

internal conditioning amplifiers. E.g. If ‘Charge’ is selected and Channel B is set to the

transducer channel, the Channel B input will be set to accept a charge input.

14.9 Interface

The electrical interface to the transducer is selected from “Charge”, “Voltage”, “Current

Excitation” and “Current Output”. This information is normally stated on the transducer

manufacturers data sheet. This information appears on the hardcopy results to ensure a

complete description of the device is available.

Interface Type Typical Transducers

Charge Piezoelectric Accelerometers

Voltage Accelerometers with built in Charge Amplifiers, Velocity and

Displacement transducers

Current Excitation Accelerometers operating on a two-wire constant current principle

(ICP)

Current Output Accelerometers which operate by providing an output proportional

to current.

In addition to the above interface types, the user may optionally specify the name for the

interface i.e. “ICP”. If a user specified name is entered, this will be printed on the results

output.

NOTE : that this entry is for the electrical interface from the transducer as opposed to that

provided from a precision amplifier to the 455 input analysers which is always a Voltage

signal.



14.10 Input Gain

The Input gain setting of the analyser channels may automatically be set whenever a

transducer configuration is loaded.

If “Manual Setting” is selected, the gain is manually set from either the “Configure

Hardware” menu, or the “Current Operating Conditions” menu.

When selecting the input gain level, consideration should be given to the sensitivity of the

input device and the amplitude of the test profile(s) being executed.

The maximum output scale of the internal conditioning amplifiers is 10V pk, therefore the

gain should be selected such that as much of the FSD of the amplifiers is utilised as possible,

without causing an over-range condition.

For example, if a transducer has a nominal sensitivity of 100mV/g and the selected test

profile is being run from 1g – 10g pk @ 80Hz, a gain of 10 may be applied as at the final test

point of 10g pk the output FSD of the input amplifiers will be met.

14.11 Nominal Sensitivity

The manufacturers stated nominal sensitivity for the transducer is entered here. It may be

used by the 455 which uses the measured sensitivity or the manufacturers stated value for the

0% or 0dB point (see 13.6.8). By depressing the “Metric Units” or “Imperial Units”

softkeys, sensitivity values may be entered in either convention with automatic conversion

between. For example, with charge interface selected a sensitivity of 10.000pC/g may be

entered. Depressing the “Metric Units” softkey this is converted to 1.020pC/m/s/s.

14.11.1 Nominal Sensitivity (Frequency)

This defines the specific frequency that the system will stimulate the test transducer at in

order to measure the device nominal sensitivity.

14.11.2 Nominal Sensitivity (Amplitude)

This defines the specific amplitude that the system will stimulate the test transducer at in

order to measure the device nominal sensitivity.

14.12 Current Output Transducers

Testing of “Current Output Transducers” also requires the following information:

14.12.1 Current to Voltage



When a “Current Output Transducer” is used, an additional external device will be required

to convert the current output into a voltage, which will be inputted into the voltage input of

the system. The current to voltage conversion setting allows the gain associated with this

conversion to be set.

14.13 Operational Range

This defines the maximum amplitude that the device may be subjected to during testing. This

value is normally detailed in the transducer manufacturers data sheet. Before testing

commences, the selected test profile is automatically checked to ensure it does not contain

any test values which would exceed this amplitude. The test profile is prevented from

running if this amplitude value would be exceeded (refer to section 13.11).

The value may be entered in either “Metric Units” or “Imperial Units” with automatic

conversion between.

14.14 Mass

The mass of the transducer is entered in “Grammes” or “Ounces”. Prior to testing, this

value is checked to ensure it is within the specified payload of the reference transducer (see

16.14). This value is also present on the hardcopy results.

14.15 Frequency Range

The “Maximum” and “Minimum Frequency” values that the transducer is to be subjected to

is entered. Before testing commences, the selected test profile is automatically checked to

ensure it does not contain any test frequencies outside of these limits. The test profile is

prevented from running if either of these limits would be exceeded (refer to section 13.11).

14.16 Warm Up

A delay may be specified for each transducer type to allow stabilisation prior to testing.

Specifying zero prevents this delay.

14.17 Temperature Range

The manufacturers operational temperature range of the transducer may be entered here. It is

not required by the Transducer Calibration System and is entered for reference purposes only.

14.18 Cal Period

The length of time before the transducer will require re-calibrating is entered here. This

entered time will appear on the lead sheet of the hardcopy results. The transducer calibration

period may be optionally set to ‘Not Required’ using the “Cal Not Required” softkey.

Section 14 - The Profiles Menu


15. Profiles Menu

The “Profiles Menu” is used to define a specific test profile of amplitude and frequency

points. The menu is entered by depressing the “Profiles” softkey from the main menu page.

This menu may only be accessed when in “Configurations” password mode (refer to

13.6.11).

With the cursor bar positioned on the “Name” line, five softkey choices are available:

15.1 List Known Profiles

By depressing this softkey, a list of the currently available profiles residing on the 455

configuration disk is presented. These are displayed in alphabetical order and may be

individually recalled by positioning the cursor bar over the required profile and depressing the

“Select” softkey.

The recalled profile may be edited if required and re-named by depressing the “Exit” softkey

where a screen message will request the user to choose between saving the new details or

leaving the previous profile details unchanged.

15.2 Make New Profile

By depressing this softkey, the profile details are cleared to default values. A completely new

profile may then be entered with saving to disk performed in a similar manner to that in 15.1.

15.3 Erase Profile

When a profile has been selected using the method described in 15.1 the profile may be

deleted using this softkey. A confirmation is requested from the user by the software prior to

the actual deletion taking place.

15.4 Save Setup

A selected profile configuration may be saved to disk by depressing this softkey.

15.5 Print Config

A text hardcopy of the selected profile may be obtained, with the output being sent to the text

device selected (see 17.3.9).

In the event of selecting “Make New Profile” or to change an existing profile name, up to 40

alpha-numeric characters may be entered with the cursor bar positioned at the “Name” line.

15.6 Profile Type

Four different types of automatic test profiles may be run by the 455 system, as follows:



15.6.1 Frequency Step

Individually specified frequencies, normally at a constant amplitude. The frequencies chosen

are normally those at which calibration values exist for the reference transducer in order to

ensure traceability.

15.6.2 Amplitude Step

Individually specified amplitudes at a constant frequency. The amplitudes chosen are

normally those at which calibration values exist for the reference transducer in order to ensure

traceability.

15.6.3 Frequency Sweep

The frequency is swept between a defined start and stop frequency at a defined linear or

logarithmic increment at a constant amplitude. The actual test frequencies are therefore

calculated by the system and will not necessarily be those at which calibration values exist for

the reference transducer.

15.7 Control Parameter

The profile may be defined as controlling “Acceleration”, “Velocity” or “Displacement”.

Dependant on the selection, the amplitude values are then entered in the relevant units.

Via a digital integration process within the 455 it is possible to run a velocity profile using an

accelerometer as the reference transducer. The 455 will convert between acceleration,

velocity and displacement units automatically.

15.8 Amplitude

When either a “Frequency Step” or “Frequency Sweep” profile is selected for generation the

test amplitude is entered here. This test amplitude will then apply to all frequency steps

unless individually edited in the frequency table.

When an “Amplitude Step” profile is selected for generation, the individual amplitude steps

are entered from a table (see 14.10)

The edit facility allows for example, a lower acceleration amplitude to apply at low

frequencies where the maximum displacement of the exciter might otherwise be exceeded.

The amplitude may be entered in either “Metric Units” or “Imperial Units” with automatic

conversion between.

15.9 Frequency

When an “Amplitude Step” profile is selected for generation, the test frequency is entered

here. This test frequency will then apply to all amplitude steps unless edited in the amplitude

table (see 15.10).



15.10 Table Editing

Individual amplitude and frequency values are entered by editing a table of test points. The

table is displayed by positioning the cursor bar at the “Amplitude” line for the “Amplitude

Step Profile” or at the “Frequency” line for “Frequency Step Profiles” and selecting the

“Edit Table” softkey.

The table of frequency and amplitude values is then displayed. The default frequency value

for the “Amplitude Step Profile” or amplitude value for the “Frequency Step Profile” is

automatically displayed for each test point entered.

Up to 80 individual frequency/amplitude combinations may be entered.

The following additional facilities are available when editing the table:

15.10.1 Insert Entry

Via the “Insert Entry” softkey, an existing table may have a new frequency/amplitude

combination inserted.

15.10.2 Delete Entry

Via the “Delete Entry” softkey, an existing table may have a frequency/amplitude

combination deleted.

15.10.3 Re-Sort Entries

Via the “Re-Sort Entries” softkey, new arbitrarily entered frequency values may be re-sorted

into ascending order.


This parameter defines the limits of the frequency (x-axis) when the results of a “Frequency

Sweep” or “Frequency Step” profile are displayed or plotted graphically. Additionally, if a

“Frequency Sweep” profile is selected, the sweep range is defined by these values.

15.12 Amplitude Range

This parameter defines the limits of the amplitude (x-axis) when the results of an “Amplitude

Step” profile are displayed or plotted graphically.

15.13 Sweep Increment

This parameter is only defined when a “Frequency Sweep” profile is being generated. The

sweep increment is defined as being Linear or logarithmic via the “Steps Per Decade” or

“Steps Per Octave” softkeys.



This parameter is interrelated with the Frequency Range (see 15.11) values. Each test

frequency point is calculated based on the entered minimum and maximum frequency and

sweep increment.

Section 15 - The References Menu


16. The References Menu

The “References Menu” is used to enter details of the reference transducers used by the 455

system.

The “References Menu” is entered by depressing the “References” softkey from the main

menu. Access to this menu is only permitted from the “Configurations” password level (see

13.6.11). With the cursor bar then positioned on the “Manufacturer” line, five softkey

choices are presented:

16.1 List Known References

By depressing this softkey, a directory of references previously entered are recalled from the

configuration disk. These are displayed in alphabetical order and may be individually

recalled by positioning the cursor bar over the required reference and depressing the “Select”

softkey.

The recalled reference details may be edited if required and re-saved by depressing the “Exit”

softkey where a screen prompt will request the user to choose between saving the new details

or leaving the previous details unchanged.

16.2 Make New Reference

By depressing this softkey, the reference details are cleared (text) or set to 0.000 (numeric).

Completely new reference details may then be entered with saving to disk performed in a

similar manner to that in 16.1.

16.3 Erase Reference

When a reference has been selected using the method in 16.1 the complete details may be

deleted using the softkey. A confirmation is requested prior to the deletion taking place.

16.4 Save Setup

A selected reference configuration may be saved onto disk by depressing this softkey.

16.5 Print Config

A text hardcopy of the selected reference details may be obtained, with the output being sent

to the currently selected text hardcopy device (see 17.3.9).

In the event of selecting “Make New Transducer” or to change an existing manufacturers

name, up to 40 alpha-numeric characters may be entered with the cursor bar positioned at the

“Manufacturers” line.



16.6 Model Number

With the cursor bar positioned at the “Model Number” line the specific reference transducer

model number may be entered.

16.7 Serial Number

With the cursor bar positioned at the “Serial Number” line the specific reference transducer

serial number may be entered.

16.8 Measured Parameter

The parameter to which the reference is sensitive is entered by depressing the “Acceleration”,

“Velocity” or “Displacement” softkey. This ensures units are in the correct format i.e. g or

m/s/s for acceleration.

The parameter entered here will also determine which of the input types is selected on the

internal conditioning amplifiers. E.g. If ‘Charge’ is selected and Channel B is set to the

transducer channel, the Channel B input will be set to accept a charge input.

16.9 Interface

The electrical interface to the reference is selected from either “Charge”, “Voltage”,

“Current Excitation” or “Current Output”.

In addition to the above interface types, the user may optionally specifically name the

interface i.e. “ICP”. If a user specified name is entered this alone will be printed on the

results output.

16.10 Current Output Reference Transducers

The use of a Current Output Reference Transducer also requires the following information:

16.10.1 Current to Voltage

When a “Current Output Transducer” is used, an additional external device will be required

to convert the current output into a voltage, which will be inputted into the voltage input of

the system. The current to voltage conversion setting allows the gain associated with this

conversion to be set.

16.11 Nominal Sensitivity

The single “Nominal Sensitivity” entry of sensitivity, frequency, test amplitude value for the

reference transducer is only used by the Transducer Calibration System if no specific

individual calibration results are entered in the reference sensitivity table. The specific

calibration points are entered by depressing the “Edit Table” softkey.



The nominal sensitivity values may be entered in “Metric Units” or “Imperial Units” by

depressing the relevant softkey.

16.12 Reference Table Editing

The table of calibration points for a reference transducer may be edited by depressing the

“Edit Table” softkey with the cursor bar positioned at the “Nominal Sensitivity” line.

The table of entered calibration values are then displayed for the selected reference transducer

or just the column headings if a totally new reference device details are being entered.

For each specific calibration test point of the reference transducer, the user may enter the

following information:

16.12.1 Frequency

The specific frequency of each calibration point. The same frequency value may be entered

more than once in order to allow different amplitude values or bands to be used.

16.12.2 Amplitude

The specific test amplitude of the calibration point or a range of valid amplitudes may be

entered. For example

4.2 (4.2 eng units)

0.1 - 3.0 (0.1 to 3.0 eng units)

Additionally the amplitude may be defined as “ALL” in which case all amplitudes at that

specific frequency are considered traceable.

16.12.3 Sensitivity

The specific measured sensitivity of the reference transducer at each calibration point.

16.12.4 Phase

The specific measured phase response of the reference transducer at the calibration point.

Up to 80 individual frequency/amplitude/sensitivity/phase point combinations may be entered

with the amplitude and sensitivity values entered in either “Metric Units” or “Imperial

Units” with automatic conversion between. The amplitude units for the reference are

globally set as either RMS, pk or pk-pk at the nominal sensitivity amplitude.

These individual values allow the 455 software to compensate for the reference transducer

values. For example, whilst a reference transducer nominal output may be defined as

3.334pC/g at 80Hz, the actual output is likely to differ slightly as the frequency changes.



By entering the specific test frequencies and the actual output at each frequency (obtained

from the reference transducer calibration values) the 455 is able to apply a correction value to

ensure this source of error is eliminated.

During testing, if a test profile is selected to run that contains test points where specific

reference transducer calibration values do not exist then a screen message is displayed

indicating:

The operator may elect to continue with the test where the individual text results will be

annotated with an asterisk at values where reference transducer calibration values do not

exist.

The following additional facilities are available when editing the table:

16.12.5 Insert Entry

Via the “Insert Entry” softkey, an existing table may have a new frequency/ amplitude/

sensitivity/ phase calibration point inserted.

16.12.6 Delete Entry

Via the “Delete Entry” softkey, an existing table may have a frequency / amplitude /

sensitivity / phase calibration point deleted.

16.12.7 Re-Sort Entries

Via the “Re-Sort Entries” softkey, new arbitrarily entered calibration values may be re-sorted

into ascending frequency order.

16.13 Operational Range

This defines the maximum amplitude the reference transducer is to be subjected to during

testing. This value is normally detailed in the reference transducer manufacturers data sheet.

Before testing commences, the selected test profile is automatically checked to ensure it

contains no test values which would exceed this amplitude. The test profile is prevented from

running if this amplitude value would be exceeded.

The value may be entered in either “Metric Units” or “Imperial Units” with automatic

conversion between.

* * * Warning * * *

The Reference is not Calibrated For At Least

One Measurement Point:

Press ENTER to Continue With Calibration, Abort to Stop



16.14 Payload

Reference Transducers usually state a minimum and maximum payload mass for the

reference calibration values to be valid. Testing a transducer where the mass value is outside

of the reference payload values can result in the tests not being traceable. The maximum and

minimum payload values are normally detailed in the reference transducer manufacturers data

sheet. Prior to any Test Profile running the test transducer mass (see 3.13) is checked against

these entered reference payload values. The operator is warned via a screen message if the

test transducer mass is outside these values.

The minimum and maximum values may be entered as “Grammes” or “Ounces” with

automatic conversion between. If both values are set to zero, the checking function will be

inhibited.


The “Maximum” and “Minimum Frequency” values that the reference transducer is to be

subjected to is entered. Before testing commences, the selected test profile is automatically

checked to ensure it does not contain any test frequencies outside of these limits. The test

profile is prevented from running if either of these limits would be exceeded.

16.16 Temperature Range

The manufacturers operational temperature range may be entered here. It is not required by

the Transducer Calibration System.

16.17 Last Calibrated / Cal Period

The date the reference transducer was Last Calibrated and the Calibration Period is entered

here. The Cal Period is a numeric number of months i.e. 12 months.

A warning will be given if the reference transducer calibration period has expired before any

testing commences. Additionally, if the calibration period will expire in less than 1 week, a

warning will also be issued.

Section 16 - The Utilities Menu


17. The Utilities Menu

The Utilities menu is entered from the main menu by depressing the softkey marked

“Utilities”. On entering the following facilities are available:

17.1 Configure Exciter

This menu allows the operational details of the calibration shaker (exciter) to be entered. The

entered information is used to ensure the shaker is not subjected to excess vibration levels

during testing, and for selected items to appear on the hardcopy information.

Upon entering “Configure Exciter”, the following information is entered:

17.1.1 Exciter

With the cursor bar positioned on the “Name” line, three softkey choices are available.

17.1.2 List Known Exciters

By depressing this softkey, a list of the currently available exciters residing on the 455

configuration disk is presented. These are displayed in alphabetical order and may be

individually recalled by positioning the cursor bar over the required exciter and depressing the

“Select” softkey.

The recalled exciter may be edited if required and re-named by depressing the “Exit” softkey

where a screen message will request the user to choose between saving the new details or

leaving the previous profile details unchanged.

17.1.3 Make New Exciter

By depressing this softkey, the exciter details are cleared to default values. A completely new

exciter may then be entered and saved to disk.

17.1.4 Erase Exciter

When an exciter has been selected, the exciter may be deleted using this softkey. A

confirmation is requested by the software from the user prior to the actual deletion taking

place.

17.1.5 Save Setup

A selected “Exciter” configuration can be saved to disk by depressing this softkey.

17.1.6 Print Config

A text hardcopy of the selected Exciter may be obtained.



17.1.7 Exciter Description

Up to 40 alphanumeric characters may be entered to describe the exciter manufacturer, model

number and serial number. This information will appear on the test result hardcopy.

17.1.8 Test Due

The date at which the exciter is due for re-calibration is entered here. Prior to any test profile

running, this date is compared with the current date. If the calibration period of the shaker

has expired or has less than one week remaining the user is warned via a screen message.

Alternatively, by depressing the “Cal Not Required” softkey, this facility may be inhibited.

17.1.9 Frequency Range

The operational maximum and minimum frequencies for the exciter are entered here. These

parameters can be obtained from the exciter manufacturers data sheet. Prior to any test

running, the test profile is checked to ensure it does not contain any frequencies outside of the

entered maximum and minimum values.

17.1.10 Max. Acceleration

The exciter manufacturers maximum acceleration limit is entered here. Prior to any test

profile running, the individual tests within the profile are checked to ensure the maximum

acceleration level will not be exceeded.

The maximum acceleration may be entered in either metric or imperial units with conversion

between using the “Metric Units” or “Imperial Units” softkey. RMS, pk or pk-pk units may

be selected.

17.1.11 Max. Velocity

The exciter manufacturers maximum velocity limit is entered here. Prior to any test profile

running, the individual tests within the profile are checked to ensure the maximum velocity

level will not be exceeded.

The maximum velocity may be entered in either “Metric Units” or “Imperial Units” with

automatic conversion between. RMS, pk or pk-pk units may be selected.

17.1.12 Max. Displacement

The exciter manufacturers maximum displacement limit is entered here. Prior to any test

profile running, the individual tests within the profile are checked to ensure the maximum

displacement level will not be exceeded.

The maximum displacement may be entered in either “Metric Units” or “Imperial Units”

with automatic conversion between. RMS, pk or pk-pk units may be selected.



The 455 software automatically converts between one amplitude parameter to another to

ensure a limit will not be exceeded. For example, if the user enters a maximum acceleration

amplitude, each test profile is checked with the frequencies entered, the maximum

displacement and velocity limits will not be exceeded by the acceleration/frequency

combinations.

17.1.13 Soft Ramping

This enables or disables an additional utility to be implemented to overcome stability

problems experienced with some long-stroke, low frequency shakers. This is at the expense

of test time.

17.2 Configure Hardware

This menu allows details of other external hardware to be entered. The entered information is

used to ensure the system components are within the stated calibration period, and for

selected items to appear on the hardcopy information.

Upon entering “Configure Hardware”, the following information is entered:

17.2.1 Last Cal

The calibration date of the 455 is stated in this field which is stored in ROM. If the

calibration has expired a warning will be given in the form of a screen message prior to any

test profile being run.

17.2.2 Cal Period

The calibration period of the 455 is entered here. The period is entered in months and is

added to the “Last Cal” date. If the “Last Cal” date plus the “Cal Period” months is greater

than the current date, a warning is given in the form of a screen message stating:

17.2.3 Conditioning

Up to 40 alphanumeric characters may be entered to describe the signal conditioning used in

the overall calibration system. Two conditioning items may be entered allowing external

conditioning amplifiers to be used for the reference and test channels, if required.

* * * Warning * * *

455 Controller

Calibration Has Expired

Press “Quit to Stop”, ENTER to Continue With Test



17.2.4 Test Due

The date at which the conditioning amplifier(s) is due for re-calibration is entered here. Prior

to any test profile running, this date is compared with the current date from the 455's real-time

clock. If the calibration period of the conditioning amplifier(s) has expired or has less than

one week remaining the user is warned via a screen message.

17.2.5 Input Gain

The 455 system incorporates internal signal conditioning amplifiers that may automatically

apply a gain of either x1, x10, or x100 for different types of reference and test transducer. If

this is the case, the gain setting to be used will be set in the ‘Transducers’ and ‘References’

configuration pages. However, if these transducer specific gain settings are set to ‘Manual’,

the gain entered here will be used throughout the test. Again, the settings of x1, x10 and x100

are available for the configuration of the internal signal conditioning amplifiers.

It is however, also possible to enter any value of gain in order to compensate for additional

external signal conditioning amplifiers (e.g. enter a gain of 2.0). If this is the case, the gain on

the internal signal conditioning amplifiers will be turned off.

This setting is duplicated in the ‘Operator’ page from the ‘Testing Configuration’ menu.

17.2.6 High Pass Filter

The internal signal conditioning amplifiers within the 455 system also allow the application

of a 5Hz HP filter for either the reference or transducer channels. If this is the case the two

“Enable” and “Disable” softkeys may be used to achieve this.

This setting is duplicated in the ‘Operator’ page from the ‘Testing Configuration’ menu.

17.2.7 Other Equipment

Up to 4 further items of equipment used in the overall calibration system may be entered with

up to 40 alphanumeric characters in the description. This allows the manufacturers model

number and serial number to be included. The entered information will appear on the test

result hardcopy.

17.2.8 Test Due

The date at which the additional items are due for re-calibration is entered here. Prior to any

test profile running, this date is compared with the current date from the 455's real-time clock.

If the calibration period of the any item of equipment has expired or has less than 1 week

remaining the user is warned via a screen message.

Alternatively, by depressing the “Cal Not Required” softkey, this facility may be inhibited.



17.3 Configure System

This menu allows the measurement and hardcopy conditions of the 455 system to be entered.

Upon entering “Configure System” from the Utilities menu, the following conditions may be

programmed:

17.3.1 Settling Time or Cycles

The settling time or cycles is the time period the complete calibration system will be allowed

to settle after a frequency or amplitude drive signal change. This time is to ensure that only a

steady state response is measured as opposed to a transient condition which may result in

errors if a measurement is triggered immediately.

The maximum of the “Settling Time” and the “Settling Cycles” will be used. For example, if

“1.000 Seconds” or “5 Cycles” is entered, at frequencies below 5Hz, the time taken for 5

Cycles of the generator drive signal will be used for the “Settling Time”. At frequencies

above 5Hz, “1.000 Second” will always be used for the “Settling Time”.

17.3.2 Measurement Time or Cycles

The measurement time or cycles is the time period each measurement will occur over. The

average value of the signal over the specified measurement time or cycles will be the value

used by the 455 in the calibration equation. The longer the system is allowed to measure, the

greater the systems noise rejection will become, due to the single sine correlation

measurement technique employed.

The maximum of the “Measurement Time” or “Measurement Cycles” will be used. For

example, if 1.000 Seconds or 5 Cycles is entered, at frequencies below 5Hz, the time taken

for 5 Cycles of the generator drive signal will be used for the “Measurement Time”. At

frequencies above 5Hz, 1.000 Seconds will always be used for the “Settling Time”.

Longer measurement times provide better rejection of noise and harmonics. Note that to meet

the stated measurement accuracy, the “Measurement Time” or “Cycles” must be equal to or

greater than 200mS or 20 cycles, see specification section 21.

17.3.3 Reference

Using the “Swop Inputs” softkey the channels used for the reference and test transducer may

be reversed, i.e. Channel A (Transducer), Channel B (Reference). This allows any error

between the two channels to be established and compensated for if required.



17.3.4 Transducer

Using the “Swop Inputs” softkey the channels used for the Reference and Transducer may be

reversed, i.e. Channel B (Transducer), Channel A (Reference). This allows any error between

the two channels to be established and compensated for, if required.

17.3.5 Phase Measurement

The phase difference between the reference and test transducer may be established by the 455.

Via the softkeys, phase information may be displayed in either “±180” or “0-360” degree

convention. Alternatively the “Off” softkey suppresses all phase information from the

display screens and hardcopy results.

Phase information is not available during the real-time display of results. Once a test profile

has run, amplitude and phase (if enabled) information may be simultaneously displayed using

the “Draw Results” softkey.

17.3.6 Display From (Max. and Min Phase Angle Ranges)

The “Minimum” and “Maximum” values for the phase axis, displayed when drawing results

may be specified when highlighting this option. The “Default” softkey allows the full range

to be reset, (i.e. -180 to +180, or 0 to 360 degrees).

17.3.7 Graph Y Axis

Two types of parameter may be selected for the test results graph y-axis. These are the

percentage or dB deviation ranges, the limits of which can be specified by the user. The

measured or stated nominal sensitivity of the transducer is the centre of the Y axis, i.e. at 0%

or 0dB (see 17.3.8).

If the dB output is selected and the phase output is not selected, the deviation is also

displayed on the tabular output results.

The percentage deviation ranges may either be displayed on the left or right hand axis of the

graph by selecting the appropriate softkey, e.g. “% on Right Axis” or “% on Left Axis”.

17.3.8 Graph Zero At

The zero sensitivity position on test result graphs may be defined as either the transducers

stated nominal sensitivity, or the actual measured sensitivity during dynamic testing. This

option is set by selecting the appropriate softkey, e.g. “Nominal Sensitivity” or “Measured

Sensitivity”.



17.3.9 Text Output

Text hardcopy may be output via the 455's RS232 “Serial” Port or “Parallel” port.

Alternatively results may be stored to a “Disk (PC Format)” for archive or loading into a PC

for incorporation into a custom certificate format. In addition “Serial PC Interface” may be

selected which enables direct data importing into a Personal Computer, when using the Beran

465 File Capture software for Windows.

The “Disable” softkey may be used to provide only graphical output.

17.3.10 Device

After selection of the Text Output port, the device protocol must be entered. Via the softkeys,

the following protocols may be selected:

PCL5 Allows a laser printer to be used i.e. HP LaserJet 4L

ASCII Standard ASCII format for most common parallel and serial

printers

ASCII For Spreadsheet Is available (for importing data into common spreadsheet

programs using comma delimiters). Graph output should be

disabled for this option.

17.3.11 Graph Output

Graphical hard copies may be output via the 455's RS232 “Serial” port or “Parallel” port.

Alternatively, results may be stored to a “Disk (PC Format)” for archive or loading into a PC

for incorporation into a custom certificate format. In addition “Serial PC Interface” may be

selected which enables direct data importing into a Personal Computer, when using the Beran

455 File Capture software for Windows.

The “Disable” softkey may be used to provide only text output.

17.3.12 Device

After a selection of the Graph Output port, the device protocol must be entered. Via the

softkeys, the following protocols may be selected.

PCL-5 Allows a laser printer to be used, i.e. HP LaserJet 4L

HP-GL Allows a 6 pen plotter to be used, i.e. HP7455A

Note: the user must verify that the selected printer supports either the PCL-5 or HPGL printer

languages. PCL-3 type printers will not print the graphical results.



17.3.13 Disk Storage

Should the user elect to store the calibration results of a test transducer to a PC format 3½”

floppy disk (either a 720K or 1.44M format), each set of results is identified as follows:

XXXXXXXX.XXX

The eight characters to the left of the full stop are automatically assigned to the test transducer

unique serial number. If less than eight characters are used, the rest of the string is truncated.

The three characters to the right of the full stop are automatically assigned to the numeric

version of calibration results for the unique test transducer. This three digit number

increments each time the unique transducer is calibrated and the results stored to the same PC

results disk.

For example, if test transducer serial number A6347 is calibrated for the second time and the

results stored to the same PC results disk the PC file name for the second results are stored as:

A6347.002

with the previous results file name being A6347.001

NOTE : that the automatic increment of the results number will only occur if the calibration

results for the test transducer are stored to the same PC disk.

17.3.14 Hardcopy Timeout

If a hardcopy device (plotter or printer) is either not connected or is not “On-Line” the 455

will be unable to output the hardcopy. The hardcopy device will also be unable to receive

output from the system at certain time if its output speed is slower than the transmission from

the 455. This is particularly noticeable with Pen Plotters and Printers with Sheet Feeders.

The “Hardcopy Timeout” value indicates how long the system should wait before assuming

that the device is no longer likely to be ready for data again. This may occur if the user turns

the hardcopy device “Off Line”.

17.3.15 Prompt For Hardcopy

On completion of a set of tests, the system can optionally prompt the user to produce a

hardcopy. When this setting is disabled, no prompt is issued.

17.3.16 Sensitivity Displayed to ‘n’ Decimal Places

The number of decimal places displayed whenever a sensitivity measurement is taken may be

defined by the System Manager. A choice of 0 to 5 decimal places is available, depending on

the resolution required.



17.3.17 Disk Free Space

Viewing the 455 “Configure System” page displays the amount of free space left on the

system disk.

17.3.18 Date and Time

The Date and Time are maintained internally via a battery-backed clock. The information is

used for output to hardcopy, and to compare with the entered calibration dates/periods of the

overall calibration system components.

The date is entered using the numeric keypad [-] key to separate the day/month/year, and the

time is entered using [.] to separate the hours/minutes/seconds.

The 455 is fully millennium compliant. Dates may be entered in the range 1/1/1980 to

31/12/2079. Years are entered as two digits, entries in the range 0 to 79 are assumed to

represent the years 2000 to 2079.

Prior to any test profile running, the current date is compared with the entered calibration due

dates of the system components. If the calibration period of a system component has expired

or has less than 1 week remaining the user is warned via a screen message.

17.4 Save Set-Up

This function is used to update a 455 configuration disk to reflect changes made to the

operating conditions. For example, if a new “Settling Time” value or hardcopy device is

modified this function allows the changes to be stored.

When the updates are complete, use the “Save Setup” softkey. A screen message will be

displayed asking the user to select either “Save Internally” or “Save To Disk” depress the

“Confirm” softkey to proceed with saving the updates or depress “Enter” to abort the update.

17.5 Additional Utilities

These may be reached by depressing the “Additional Utilities” softkey from the “Utilities”

menu.

17.5.1 Access Codes

Three levels of access to the 455 system functions are provided as follows:

17.5.1.1 Operational Mode 1

Allows access to all “Test” menu functions with the exception of altering the “External

Gain” settings. Within the “Utilities” menu, access to the “Phase Measurement”, “Graph Y

(%) Tolerance Range” and all “Hardcopy” functions is permitted.



No access to the “Transducers” menu, “Profiles” menu or “References” menu permitted or

access to the “Configure Exciter”, “Configure Hardware”, “Save Setup” or “Additional

Utilities” menus within the “Utilities” menu permitted.

17.5.1.2 Operational Mode 2

As Operational Mode 1 with the exception that the “External Gain” settings (see 17.2.5)

within the “Current Operating Conditions” menu page may be altered.

17.5.1.3 Configuration

Full access to all facilities allowed. The three passwords defining the Access Modes may be

entered or modified.

17.5.1.4 Password Modification

The three individual passwords are modified by positioning the cursor bars at the relevant

access mode and entering the alphanumeric password which may be up to 9 characters in

length.

NOTE : That the passwords are case and space sensitive, i.e. if a password entered as

“Level1”, then “level1” will not be accepted as the password when changing access level as

described in 13.6.11.

17.5.2 Format Data Disk

Transducer results may be stored to either a 720KByte or 1.44MByte PC format 3½” disk.

These may either be formatted by a PC or by the 455 by selecting the appropriate disk format

size.

17.5.3 Format Config Disk

The 455 system configuration disk is not the same format type as PC disks. The user can

format configuration disks using the appropriate disk size softkey with the highlighter cursor

bar at this location. The config disk may be either 720KByte or 1.44MByte.

17.5.4 Config Disk Copy

A copy of the configuration disk may be made using this utility. Before a disk copy is made

the user must format the destination disk, using the “Format Configuration Disk” in the

“Additional Utilities” menu.

NOTE : In all cases the target disk (working disk) will automatically be reformatted before

copying. To avoid fatal errors, ensure master disk is write protected before copying.



17.5.5 Copying

Insert the configuration disk into the floppy disk drive and depress the “Config Disk Copy”

softkey. Follow the screen instructions which guide the user into inserting the source and

target disk (working disk).

When copying a 455 configuration disk the target disk (working disk) will be automatically

reformatted before copying.

17.6 IEEE Slave Address

The 455 can be operated in an IEEE Slave Mode, at the address specified by the user. This

mode can be enabled by using the ‘IEEE Remote’ softkey. When in this mode the front panel

is disabled. IEEE mode can be terminated by sending the ‘Go To Local’ IEEE command,

refer to section 18.9.

Section 17 - IEEE-488 Remote Control


18. IEEE-488 Remote Control

If required, the 455 system may be utilised as an IEEE slave device. During operation in this

mode the front panel is disabled and the basic measuring functions of the instrument are

initiated over the IEEE interface.

18.1 IEEE Address

The IEEE address of the instrument is set in the “Additional Utilities” menu (refer to section

17.6) and is stored internally when the unit is turned off. The same address will be reset when

the unit is turned on again, unless the system configuration is loaded from and a different

address has been stored (see Section 17.4).

18.2 IEEE Command Format

All commands used by the instrument are simple ASCII strings, which are generally

mnemonics of their function. For example, to turn the generator on, use the command

“GON”. Strings may be terminated either by EOI, or by a line feed character.

The general format of IEEE commands is as follows :-

CCC P1,P2,P3;CCC P1,P2...

Where: CCC is the command mnemonic

P1 is the first optional parameter, separated by a space from the mnemonic

P2 and P3 are further optional parameters, separated from each other by

commas

; Separates commands on the same line from each other

The current setting of any parameter may be requested, by preceding the mnemonic with a '?'.

The system will respond with the appropriate command, just as would be sent to set the

parameter.

18.3 Parameter Formats

In the description of the commands, the argument(s) are specified as follows

F Floating Point (including exponential)

(e.g. 1.0 or 1.56E-3)

I Integer (e.g. 5 or 145)

C Channel Letter (A or B)

UI Units type 1 (V or E) (Volts/EU)

S String of Characters

U2 Units type 2 (S or C) (Seconds or Cycles)



18.4 Generator Commands

Parameter Code Argument

Frequency GFR F (Hz)

Amplitude GAM F (V RMS)

Bias GBI F (V)

Waveform GWF I (0 = Sine)

(1 = Square)

(2 = Triangle)

Generator On GON -

Generator Off GOF -

Closed Loop Channel CCH C (A or B)

Closed Loop Target CTA F,U1

Maximum Generator Output CMG F (V)

Closed Loop On/Off CLP I (0 = On)

(1 = Off)

Closed Loop Error CER F

Soft Start GSN I (0 = On)

(1 = Off)

Soft Stop GSF I (0 = On)

(1 = Off)

Hold GHO I (0 = Off)

(1 = at 0 Deg)

(2 = at 90 Deg)

(3 = at 180 Deg)

(4 = at 270 Deg)

(5 = Instantaneous)

18.5 Analyser Commands


Integration Time AIT F,U2

Measurement Delay AMD F,U2

Auto Integration AAI I (0 = Off)

(1 = Short)

(2 = Long)

Auto Integrate Channels AIC C,I (0 = On)

(1 = Off)



Channel Range ACR C,I (0 = Auto)

(1 = 30mV)

....

(4 = 30V)

Channel Coupling ACC C,I (0 = AC)

(1 = DC)

Channel Selection ARE C,I (0 = On)

(1 = Off)

Channel Input Type ACT C,I (0 = Single Sided)

(1 = Differential)

Harmonics HAR N (1 = Off)

....

(16 = 16th)

NOTE : When requesting the current setting of one of the channels parameters, it is

necessary to specify which channel is required. For example, to check the channels input type

on channel B, send the following string

?ACT B

18.6 Measurement Control Commands


Stop Measuring MST -

Single Measurement MSI -

Repeat Measurement MRE -

18.7 Sweep Control Commands


Lowest Frequency SFL F

Highest Frequency SFH F

Sweep Increment SIN F, I (0 = Hz)

(1 = Step/Oct)

Sweep Status SST I (0 = Up)

(1 = Down)

(2 = Hold)

(3 = Off)

(4 = Step)



18.8 Interface Control


Parallel Poll Response PPR I

Poll Generation Mask PGM I

Bit0 End of Measurement

Bit1 End of Sweep

Bit2 End of Output

Output Format Terminator OFT I (0 = EOI)

(1 = LF/EOI)

(2 = LF)

18.9 Miscellaneous Commands


Go to Local GTL -

Full Reset INI -

The GTL function returns the 455 into front panel mode.

Full reset restores the unit to the power on state.

18.10 Enquiry Commands


Report Instrument Status ?STS -

Returns - STS GFR (F),MEA (c1),SWE (c2)

GFR -> current frequency

MEA -> measurement status, c1 = (Stop, Single, Repeat)

SWE -> sweep status, c2= (Up, Down, Hold, Off, Step)

Last Data Set ?ODC - Returns last set of results in

Cartesian format

?ODP - Returns last set of results in

Polar format



18.11 Obtaining Results

Two commands are available for obtaining results from the unit ?ODC (output last set of

results (Cartesian)) and ?ODP (output last set of results (Polar)).

The output last data command (?ODC) sends only the last set of results, in condensed format,

to the IEEE interface. Results for the two channels are sent, irrespective of any channels

which have been de-selected with the ARE command.

18.11.1 Condensed Results Format

The format in which the results are presented depend on how they were requested. The two

types of condensed format are as follows :-

18.11.1.1 Output from the ?ODC command

The results are always in Cartesian format, and are in the following format :-

F, MPX, 1, R, C, 2, R, C

where F is the frequency

MPX is the multiplexer number

R is the real part of the result

C is the complex part of the result

18.11.1.2 Output from the ?ODP command

The results are always in polar format, and are in the following format :-

F, MPX, 1, M, P, 2, M, P

where F is the frequency

MPX is the multiplexer number

M is the magnitude part of the result

P is the phase part of the result

18.12 Obtaining Status Information

Two mechanisms are available for checking the status of the instrument, the ?STS command,

and the Serial Poll mechanism. The status (?STS) command returns basic information

concerning the current state of the unit. The Serial Poll function, described in the next

section, is much more powerful.



18.13 Serial and Parallel Polls

The instrument may be configured to generate a service request when a particular operation

completes. The instrument supports both parallel and serial polling, to allow the host to

determine which of the devices on the IEEE requested service.

18.13.1 Serial Poll

The instrument may be serially polled at any time. It will respond by outputting a status byte,

which gives the current state of the instrument. Each bit in the status byte has a specific

meaning when set, as follows :-

Bit 0 - End of Measurement

Bit 1 - End of Sweep

Bit 2 - Not Currently Used

Bit 3 - IEEE Output Available



Bit 6 - Requesting Service


As an example, the value 5 (Binary 00000101) has the following meaning :-

Measurement Completed

Sweep In Progress

Hardcopy Completed

No IEEE Output available

18.13.2 Service Request

A service request may be generated on any or all of :-

End of Measurement

End of Sweep

In order to inform the instrument that a service request is required, the PGM command must

be issued, with the appropriate mask value given as a parameter. A bit must be set for each

event for which a service request is required, as defined for the serial poll response. For

example, to inform the instrument that service request is required on End Of Sweep, send the

following command :-

PGM 2

An active Service Request is cleared by conducting a serial poll of the instrument.

To disable the service request function, send the PGM command, with a 0 as the parameter.



18.13.3 Parallel Poll

The unit can be configured to give a response to a parallel poll, on a particular IEEE line,

when the unit is requesting service. The line that is to be used is set using the PPR command,

for example :-

PPR 3

will result on a parallel poll response being set on IEEE line 3

The parallel poll response may be disabled by sending the PPR command, with 0 as the

parameter.

18.14 IEEE Command Errors

Unrecognised or incorrect IEEE commands will result in the instrument producing a warning

beep, and an accompanying error message on the status line.

18.15 Example IEEE Control Program

The following program is written in HP Basic, as used on the Hewlett Packard 86 series

micro-computers. The program configures a sweep then executes it in single step

measurements displaying the results after each measurement.

10 REM Reset the 455 to clear current configuration

20 OUTPUT 708 ;”INI”

30 WAIT 3000

100 REM Set Generator Parameters

110 OUTPUT 708 ;”GFR 100;GAM 1;CCH A;CLP 0”

120 REM Generator Frequency 100Hz

130 REM Generator Amplitude 1V RMS

140 REM Closed Loop Control Channel A

150 REM Closed Loop Control On

200 OUTPUT 708 ;”SFL 100;SFH 1000;SIN 20,2;SST 0”

210 REM Set Sweep Parameters

220 REM Start Frequency to 100Hz

230 REM Stop Frequency to 1kHz

240 REM Steps at 20 Steps/Decade

250 REM Set Sweep ‘UP’

300 OUTPUT 708 ;”GON”

310 REM Turn Generator On

350 REM Set 20 Decade Loop

360 LET S=1

370 CLEAR



380 DISP “SWEEP IN PROGRESS”

400 REM Execute A Single Measurement

410 OUTPUT 708;”MSI”

500 REM Read Data From Measurement

510 DIM A$[9],B$[2],C$[2],D$[11],E$[11]

520 OUTPUT 708 ;”?ODC”

530 ENTER 708 : A$,B$,C$,D$,E$

600 REM Display Results From Measurement

610 DISP “WHEN FREQUENCY=“;A$;” REAL PART=“;D$;” AND IMAGINARY

PART=;E$

620 REM Pause Before Continuing

630 DISP “PRESS ENTER BEFORE CONTINUING”

640 INPUT M$

650 CLEAR

660 DISP “SWEEP IN PROGRESS”

700 REM If All The Steps Have Passed Then Do Not Repeat Cycle

710 IF S=21 THEN GOTO 800

720 LET S=S+1

730 GOTO 400

800 DISP “SWEEP HAS FINISHED”

810 OUTPUT 708 ;”GTL”

820 END

Section 18 - Errors And Reducing Measurement Errors


19. Reducing Measurement Errors

Errors may occur during the operation of the instrument for a number of reasons. The most

common are due to incorrect data entry, however if a more serious system error is detected,

the unit will sound a long tone, and display an error message at the top of the screen for

around 3 seconds. If the over-range LED’s on the front panel of the instrument become

illuminated, the maximum output scale of the internal conditioning amplifiers will have been

exceeded, potentially creating a measurement error. In order to overcome this, either the input

gain for the channel, or the vibration amplitude level of the test must be reduced.

19.1 Test transducer Mounting

The following points should be considered when mounting test transducers to the reference

shaker table

1. Mechanical coupling of the transducer under test to the shaker table.

2. Triboelectric effects of moving cable.

19.1.1 Mechanical Coupling

At higher frequencies (above 1kHz) even relatively high acceleration levels correspond to

very small mechanical displacements (i.e. 10g and 2kHz gives 0.001mm peak to peak

displacement). Most materials at these frequencies tend to behave in an ‘elastic’ manner and

the shaker table is no exception. Depending upon the mounting method, the amount of

mechanical coupling between reference accelerometer and device under test can be variable.

The ideal method of coupling is to have no interface material between the two devices but

this is usually not practical. The best compromise is to mount the device under test with a

screw stud, immediately over the reference accelerometer in the centre of the shaker table. A

light coating of thin oil on the mating faces further aids coupling. It is also important for

reproducibility to use the recommended mounting torque, specified by the manufacturer of

the transducer under test.

At lower frequencies, it is acceptable to use adhesive mounting for accelerometers.

Where larger accelerometers are to be calibrated or where multiple fixings are used, it is usual

to calibrate over a lower frequency band as the vibration ‘platform’ is only calibrated on the

reference surface of the reference accelerometer and at higher frequencies, a significantly

different vibration level could be produced at the active element of the device under test,

particularly if an interface plate of less rigid material has been introduced.

19.1.2 Triboelectric Effects

Where piezo-electric accelerometers are being tested, the cable to the charge converter must

be considered. A special cable type is normally used with a graphite material impregnated

within its screen to minimise the changes in capacity exhibited when the cable is moved or

flexed.



Particularly at very low frequencies with corresponding high displacements and where low

sensitivity accelerometers are being used, the cable induced noise can introduce a significant

error. Unfortunately, this noise is of the same frequency as the vibration generator and can

either add or subtract to the wanted signal depending upon the phase of the bending mode of

the cable.

This cable effect can be minimised by controlling the cable flexing by supporting it in such a

manner that movement is minimised, bend radii are large as possible and in extreme cases,

ensuring that the accelerometer cable does not change direction after connecting to the

accelerometer. Adhesive tape is useful for support and for reproducibility the support scheme

should be noted and replicated for future tests.

Care should be taken to avoid earth loops in turn affecting the measurement results. The body

of the shaker tables may be connected to earth. If the body of the transducer under test is

connected internally to the screen of its output low noise cable, an earth loop can be formed.

This can be avoided by fitting an insulating plate (not supplied) between the reference

transducer table and the transducer under test.



20. Calibration

The ‘455 Vibration Transducer Calibration System’ comprises of a precision measurement

system allowing the vibration outputs from the ‘Reference’ and ‘Transducer under Test’ to be

measured using the Sine Correlation Technique, as well as two signal conditioning amplifiers

allowing input gain to be applied to the transducer type selected. An overview of the 455

systems internal measurement and amplification circuits is given in figure 6.

Calibration of the instrument allows each of these components to be tested independently,

ensuring that full traceability is gained through the known behaviour of each of the system

components.

20.1 Measurement Circuits Calibration

The measurement circuit within the 455 System employ a calibration technique whereby

correction values are stored in non-volatile memory. During normal operation the correction

values are digitally applied to the acquired data. To enter the calibration mode of the 455

system switch the instrument off, insert the calibration key into the keyswitch, and turn to the

“Cal” position. When the 455 is switched on, calibration mode is entered.

A fully automatic calibration may be carried out by means of a suitable IEEE Digital

Voltmeter. The 455 is able to control the DVM via the IEEE, and set the correct range, trigger

a reading, receive the DVM reading. The results from the DVM are internally compared with

the selected output from the 455 and if any error is established, a correction value calculated

and stored. When the 455 is returned to normal use from the calibration mode the correction

values are automatically applied to the acquired data.



If a suitable non IEEE DVM is available, calibration may be performed manually by entering

the required information using the 455 front panel softkays. The 455 sequences through the

calibration points with the calibration engineer entering the DVM reading at each step. As per

the automatic calibration, if any error is established a correction value internally calculated

and stored.

The calibration results may be printed via either the 455 Centronics parallel port or to a PC

format floppy disk, allowing the calibration engineer to insert the calibration results into a

preferred certificate format.

CAUTION: Calibration of the measurement circuits requires the generator output of the

system to be tested. Due to this, it is important that the calibration shaker is

disconnected from the system to prevent it from being operated in an open loop

mode which may potentially cause damage.

20.1.1 Calibration Mode

When the keyswitch is turned to the “Cal” position, the engineer is able to select three modes

of operation.

20.1.1.1 Calibrate

In “Calibrate” mode, the 455 will establish any errors within the measurement circuits and

will internally calculate a correction value. The correction value is subsequently applied and

then each parameter checked i.e. verified to ensure the parameter is adjusted. At the end of

the complete calibration sequence, the calibration engineer is able to permanently store the

correction values by depressing the softkey “Calibrate Unit”. Alternatively, the 455 may be

left unchanged i.e. the correction values from the previous calibration will apply.

20.1.1.2 Verify

The “Verify” mode allows all the steps of the “Calibrate” mode to be carried out but without

correction values being calculated and applied.

20.1.1.3 Un-Calibrate

The “Un-Calibrate” mode removes all digital correction values stored in the 455 non-volatile

memory. This mode is used when hardware repairs are being carried out or if the “Automatic

Calibration” functions cannot adjust the unit within specification. Manual calibration will

then be required. If the “Un-calibrate” softkey is depressed, confirmation is required before

the correction values are erased.

20.1.2 Automatic Calibration

20.1.2.1 Equipment Required

455 Calibration Key

IEEE Interface Lead



BNC to 4mm Terminal Cable (for DVM)

2 off BNC to BNC Cables

2 off BNC “T” Connectors

Parallel port printer i.e. NEC Pinwriter P20 and cable

IEEE DVM

Drivers for popular calibration DVM's exist in the 455. Models with an integral frequency

counter i.e. Datron 1281/1271 (with A.C. option) are preferred as these allow a fully

automatic calibration of all parameters. Models without an integral frequency counter are

able to automatically perform all calibration steps with the exception of the “Generator

Frequency”. A non IEEE Frequency Counter with the ability to measure frequencies in the

range 20Hz - 100kHz, 6 digit resolution and frequency error <0.01%.

The user may establish the currently supported IEEE DVM's by entering the calibration

sequence in the 455 (see Section 20.1.2.2). The IEEE DVM's supported will be listed on the

instrument display.

20.1.2.2 Automatic Calibration Method

For automatic calibration the following procedure should be followed:

1. With the instrument switched off, insert the calibration key into the keyswitch on the

rear of the 455 and turn to the “Cal” position. Also, ensure that both of the toggle

switches on the rear panel are set into the ‘SINGLE’ position.

2. Switch on the 455 and allow the instrument to stabilise for a minimum of 2 hours.

3. Connect the IEEE lead from the 455 to the calibration DVM. Ensure the DVM IEEE

port is set to TALK and LISTEN modes and establish the DVM IEEE address (see

DVM handbook).

4. Switch on the DVM (and Counter if required) and ensure the instrument has stabilised

for sufficient time to meet the manufacturers specification (refer to the manufacturers

handbook).

5. Follow the 455 screen instructions which guide the calibration engineer in connecting

the analogue signals, selecting the IEEE DVM and address, calibration/verify mode and

hardcopy/PC disk result storage.

6. On completion of automatic calibration, a message is displayed indicating whether the

unit has failed any calibration tests.

7. After all sequences have been performed the unit may be returned to normal 455

operation by turning the keyswitch to “Normal” and following screen instructions.

20.1.3 Manual Calibration




455 Calibration Key

BNC to 4mm Terminals Cable (for DVM)

2 off BNC to BNC Cables

2 off BNC “T” Connectors

Parallel Port Printer i.e. NEC Pinwriter P20 and Cable

DVM with A.C. performance equivalent to Datron 1271 or 1281 between 40Hz and

100kHz

Frequency Counter (if not internal to DVM) with the ability to measure frequencies in

the range 20Hz - 100kHz, 6 digit resolution, frequency error <0.01%.

20.1.3.2 Manual Calibration Method

For manual calibration the following method should be followed:

1. With the instrument switched off, insert the calibration key into the keyswitch on the

rear of the 455 and turn to the “Cal” position.

2. Switch on the 455 and allow the instrument to stabilise for a minimum of 2 hours.

3. Switch on the DVM (and Counter if necessary) and ensure the instrument stabilises for

the manufacturers recommended time period (see manufacturers handbook).

4. Follow the 455 screen instructions which guide the calibration engineer in connecting

the analogue signals, calibration/verify mode (see 20.1.1) and hardcopy/PC result

storage. During calibration the system will display the computed error for 2 seconds

before moving on to the next measurement.

5. After all sequences have been performed the unit may be returned to normal 455

operation by turning the keyswitch to “Normal” and following screen instructions.

20.1.4 Result Hardcopy

Calibration/Verification results may be output to hardcopy via the parallel port. Each

function tested is listed with pre-calibration value, absolute error and error percentage. Any

results falling outside of the specification are marked with an asterisk.

20.1.4.1 Result Storage To PC Disk

Calibration/Verification results may be stored onto a 720K or 1.44M PC formatted disk. This

allows results to be merged into a standard result certificate. Each set of results is annotated

with the 455 serial number as follows:

CAxxxxxx with xxxxxx being the instrument serial number.

If more than one set of results for the same instrument is stored on a single disk the file name

is annotated in ascending order i.e. 01, 02 etc.



20.2 Input Amplifier Calibration

The input amplifier circuits within the 455 system are independent to the measurement

circuits and their calibration may be verified and updated if necessary. Both calibration and

verification is possible for the two input channels. The circuit incorporates three switched

front-end amplifiers for interface with Current Output, Voltage and Charge type devices

where the charge amplifier has an independent unity gain adjustment trimmer. Additionally,

two gain stages of x10 are available to enable input amplification of x10 and x100 to be

applied. Each of these gain stages may be calibrated in terms of zero offset adjustment and

gain. Although no adjustment is allowed, the functionality of the 5Hz HP should also be

verified as a part of the calibration procedure.


BNC to 4mm Terminals Cable (for DVM)

BNC to BNC Cables

Calibration DVM

Calibrated 1000pF Capacitor (±0.05%)

Section of Low Noise Lead

Calibration Signal Generator

20.2.1.2 Calibration Method

The procedure below may be used in order to verify the calibration of the systems input

amplifiers. The same procedure may be used for both the channel A and channel B input

amplifiers:

WARNING: This procedure should only be executed by a competent person, as removal of

the instruments protective panels is required.

WARNING: The operator is not required to touch any internal part of the 455 at any time

throughout the execution of the calibration procedure as hazardous live

components may be present on a) the rear of the EL front display and b) at the

power connector inputs to the power supply.

When performing calibration of the input amplifier cards, it may be necessary to adjust the

pre-set potentiometers installed on them. When viewed from the front, the input amplifier

cards are positioned on the top right hand side of the 455 system, where the channel A

conditioning card is positioned next to the side panel of the instrument. The position of the

potentiometers on the conditioning card is detailed in figure 7.



Initial Set-Up (Procedure to be used prior to all other tests)

1. Remove all sources of mains power from the unit and disconnect all other signal

connections.

2. Remove the lid from the 455 instrument by releasing the two hex head screws from

the feet at the top of the rear panel of the instrument. The earth tag crimp must also

be removed, which grounds the lid of the instrument to the chassis.

3. Power up the instrument. (This step is only required if calibrating the charge input,

or either of the gain stages)

4. Select the ‘Reference’ channel to be ‘Channel A’ within the ‘Configure System’

menu from the ‘Utilities’ page. Ensure that the ‘5Hz Filter’ for the reference

channel is disabled.

Voltage Input Calibration

1. From the instruments main menu, enter the ‘References’ configuration page and

select ‘Voltage’ as the input interface type and ensure that the input gain setting is

set to ‘x1’. This will select a voltage type input with a gain of x1 for channel A.

2. Using the signal generator, enter a sinusoidal signal of 3V RMS @ 400Hz into the

Channel A ‘Voltage HIGH’ input, ensuring that the single/differential switch is set

in the single position.

3. By connecting the Calibration DVM (AC) to the Channel A monitor output, verify

a gain of 1.0 ±0.25%.

4. Conduct further tests if necessary using the pass/fail criterion detailed in table 1

below. It is recommended that frequency test points are chosen to match those at

which the reference transducer normally used with the system has been calibrated,

in order to provide traceability throughout the entire measurement system.

ICP or Voltage I/P - Frequency Response (I/P > 10% FSD)

Magnitude 5Hz – 5kHz : 0.25% 1Hz – 25kHz : 1% 0.5Hz – 50kHz : 5%

Phase 5Hz – 2.5kHz : 2o 1Hz – 25kHz : 12.5o 0.5Hz – 5kHz : 25o Table 1

Current (ICP) Input Calibration


select ‘Current Excitation’ as the input interface type and ensure that the input gain

setting is set to ‘x1’. This will select an ICP type input with a gain of x1 for channel

A.


Channel A ‘I’ input.



3. By connecting the Calibration DVM (AC) to the Channel A monitor output, verify

a gain of 1.0 ±0.25%.





Charge Input Calibration


select ‘Charge’ as the input interface type and ensure that the input gain setting is

set to ‘x1’. This will select a Charge type input with a gain of x1 for channel A.


Channel A ‘Q’ input, through a 1000pF Capacitor.

3. By connecting the Calibration DVM (AC) to the Channel A monitor output, verify a

gain of 1.0 ±0.25%.

4. If adjustment is required, use a small flat blade screw-driver to adjust the gain

through VR1. The positioning of VR1 is detailed in figure 7.





Charge I/P - Frequency Response (I/P > 10% FSD)

Magnitude 5Hz – 5kHz : 0.25% 2.5Hz – 25kHz : 1% 1Hz – 50kHz : 5% 0.5Hz – 1Hz : 0-20%

Phase 50HZ – 2.5kHz : 2o 5Hz – 10kHz : 10o 2.5Hz – 25kHz : 22½o 1Hz – 50kHz : 45o 0.5Hz – 1Hz : 90o Table 2

Zero Offset Calibration (Gain Stages)




2. Short out the ‘Voltage HIGH’ input for channel A, ensuring that the

single/differential switch is set to the single position.

3. By connecting the Calibration DVM (DC) to the Channel A monitor output verify a

zero offset of <1mV, adjust VR2 accordingly. The position of VR2 is detailed in

figure 7.



set to ‘x100’. This will select a voltage type input with a gain of x100 for channel

A.



5. Ensuring that the voltage input is still shorted, verify a zero offset of <10mV,

adjust VR3 accordingly. The position of VR3 is detailed in figure 7.

Gain Calibration (x10)




2. Using the signal generator, enter a sinusoidal signal of 300mV RMS @ 400Hz into

the Channel A ‘Voltage HIGH’ input, ensuring that the single/differential switch is

set in the single position.

3. By connecting the Calibration DVM (AC) to the Channel A monitor output verify a

gain of 10.0 ±0.25%, adjust VR4 accordingly.

Gain Calibration (x100)



set to ‘x100’. This will select a voltage type input with a gain of x100 for channel

A.

2. Using the signal generator, enter a sinusoidal signal of 30mV RMS @ 400Hz into

the Channel A ‘Voltage HIGH’ input, ensuring that the single/differential switch is

set in the single position.

3. By connecting the Calibration DVM (AC) to the Channel A monitor output verify a

gain of 100.0 ±0.25%, adjust VR5 accordingly.

Section 20 - 455 Interface Connections


21. Interface Connections

21.1 Serial Interface

Connector - 25 Way D Type Plug

Flow Control - Hardware

Connector Pinning :-

1 Ground

2 Transmitted Data

3 Received Data

4 Request To Send

5 Clear To Send

7 Signal Ground

21.2 Parallel Interface

Connector - 25 Way D Type Socket

Connector Pinning :-

1 STROBE/

2 D0

3 D1

4 D2

5 D3

6 D4

7 D5

8 D6

9 D7

10 ACK/

11 BUSY

12 PE

13 SLCT

14 AUTOFD/

15 ERROR/

16 INIT/

17 SLCT IN/

18-25 GROUND

21.3 Keyboard

Connector - 6 Way Miniature DIN Socket

Supports PS/2 Standard

Section 20 - 455 Interface Connections


Connector Pinning:-

1 - DATA

2 - N/C

3 - GROUND

4 - +5V

5 - CLK

6 - N/C

21.4 Shaker

The two pin shaker output connector should be used for the connection of an external shaker

system.

Section 21 - 455 Specification


22. 455 System Specification

22.1 Generator

Frequency Range - 0.1Hz to 100kHz

Resolution - 1 part in 10000

Error - <0.05%

Amplitude Control Parameter - Acceleration, Velocity or Displacement

Increment - User defined

Units - Metric or Imperial

Range - 10mV to 10V RMS

Increment - Linear

Resolution - <0.2mV RMS

Accuracy - > 99% ±10mV

Waveform - Sine

Output Impedance - 50Ω

Distortion (sinewave) - < 1%

Connection - BNC

22.2 Shaker Output (Where different from generator)

Frequency Range - 1Hz to 50kHz (-3dB)

Amplitude Range - 20mV to 20V RMS

Output Power - 120W RMS

Slew Rate - 30V/μs

Maximum Output Voltage - 20V RMS

Maximum Output Current - 5.5A RMS

Connection - 2 Way, Size 14, 62GB series connector

22.3 Results

Test Channel, divided by Reference Channel

Processing

Numeric Integration

Minimum - 1 cycle

Maximum - 30000 cycles

Measurement Delay

Minimum - Zero

Maximum - 30000 cycles



Results - Text or Graphic

Amplitude or Phase

Resolution Amplitude - 0.001 Units

Phase - 0.001º

22.4 Measurement Channels

Two independent channels operating in parallel

Input Configuration

Input types - Charge, Differential Voltage, Piezotron/ICP

Input Dynamic Range - 10,000mV/10,000pC

Input Gain - x1, x10, x100

Input HP Filter - 5Hz (24dB/Octace, Butterworth)

ICP Compliance - +30V @ 4.7mA

Differential Voltage

Input Impedance - 1Mohm

Common Mode

Rejection - 10V

Cross Channel

Isolation - >85dB

Error

Temperature 20C ± 10ºC

Integration >200 ms or 20 Cycles

Input >10% FSD

Analysers

Amplitude Phase

Up to 1kHz - ±0.2% ±0.25°

1kHz - 5kHz - ±0.3% ±0.5º

5kHz - 20kHz - ±0.5% ±1.0º

20kHz - 50kHz - ±0.7% ±3.0º

>50kHz - ±1% ±5.0º



Input Amplifiers

Amplitude Phase

Voltage or ICP

5Hz – 2.5kHz - - - 2º

5Hz – 5kHz 0.25% - - -

1Hz – 25kHz 1% 12.5º

0.5Hz – 50kHz 5% 25o

Charge

50HZ – 2.5kHz 2º

5Hz – 5kHz 0.25%

5Hz – 10kHz 10º

2.5Hz – 25kHz 1% 22.5º

1Hz – 50kHz 5% 45º

0.5Hz – 1Hz 0-20% 90º

5Hz HP Filter

0.625Hz -72 12dB - - -

1.25Hz -48 6dB - - -

2.5Hz -24 3Db - - -

5.0Hz -3 1dB 180º

10.0Hz 0 ±0.25dB - - -

20.0Hz 0 ±0.1dB - - -

50.0Hz 0 ±0.1dB - - -

100.0Hz 0 ±0.1dB - - -

Ranges

Q I V

1mV/pC

1mV/mV

1mV/mV

10mV/pC

10mV/mV

10mV/mV

100mV/pC

100mV/mV

100mV/mV

Connections

Differential Voltage - Differential BNC, Switch Selectable

ICP - BNC

Charge - Microdot

Monitor (O/P) - BNC



22.5 Transducer Test Profiles

Type - Frequency Step, Frequency Sweep or Amplitude Step

Control - Acceleration, Velocity or Displacement

Amplitude


Test Point

Per Profile - Up to 80

Sequential Test - Up to 4

22.6 Reference Transducer

Measured

Parameter - Acceleration, Velocity or Displacement

Interface - Charge, Voltage, Current Excitation, Current Output

(Dependent on External Amplifier)


Entered - Frequency, Test Amplitude, Measured Sensitivity, Measured Phase

Calibration Calibration Date

Data

Calibration

Data Points - Up to 80

22.7 Test Transducer

Measured

Parameter - Acceleration, Velocity or Displacement

Interface - Charge, Voltage, Current Excitation or Current

Output. (Dependent on External Amplifiers)




22.8 Interfaces

Serial Port Type - RS232

Flow Control - DTR

Speed - 9600 baud

Parallel Port Type - Centronics Compatible

Floppy Disk Type - 3.5 inch

Capacity - 720K/1.44M

Text Output Parallel, Serial or PC format disk

Device - PCL-5, ASCII or ASCII Spreadsheet

Format

Graph Output Parallel, Serial or PC format disk

Device - PCL-5 or HP-GL

IEEE 488 port Mode - Slave

Data Rate - 500 kbytes/sec

Functions Implemented - SH1,AH1,T5,TE5,L3,LE3,SR1,RL1,

PP1,PP2,DC1,DT1,C1-C4,C9

22.9 General

Power Supply Voltage - 85-265V A.C. Wide Range

Frequency - 45-450Hz

Consumption - <250VA

Physical Width - 450mm

Height - 270mm

Depth - 470mm

Profile - 6U. For 19” rack mounting

DIN 41494

Weight - 22Kg

Environmental Operating Temp. - 0 to +50°C

Storage - -30 to +70°C

Specification - 20°C ±10°C

Humidity,

Non Condensing - 95% @ 40°C

Section 22 - Troubleshooting

Issue 1.1.0 January 2001 Page 23.1

23. Beran 455 Trouble Shooting Guide

Problem Remedy

During testing the display has the error

message “Output Rising Above

Maximum”.

1. Increase external power amplifier gain

(If fitted).

2. Check profile configurations.

3. Reference/Transducer Input Gains set

to correct settings. If no Input Gain

applied set Input Gain to 1mV/mV.

During testing the display has the error

message “Output Falling Below

Minimum”.

Decrease external amplifier gain(If

fitted).

When starting a test the message

“Reference Out Of Cal” displayed.

Calibration of reference transducer has

expired and requires re-calibrating.

Calibration results to be entered into

reference page, calibration points to be

entered into reference table.

Power amplifier protection circuit trips

out.

1. Closed loop not made.

2. Enable soft ramping for testing below

20Hz.

How to import results into a spreadsheet. In the 455 Utilities, Configure System set

the text output to be ASCII Spreadsheet

format. The file is stored as a comma

delimited file and will require opening

with the delimiter type set as commas.

When attempting to load transducers,

references, profiles or storing

configurations to disk “The disk is not the

configuration disk” is displayed.

Install configuration disk containing

transducers, references, profiles and other

system settings.

When starting tests the message

“Response from reference may not be

present or exciter may not be connected”.

1. Check generator output connection is

made.

2. Check input is made to reference

channel.

3. External power amplifier gain too low

or not switched on(If fitted).

4. External Signal conditioning

equipment for reference channel

connected and powered on.

User’s Notes

beran 455 system

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