Data Acquisition and Logging with NI CompactDAQ and LabVIEW

SignalExpress

Presented by Stephen PlumbBranch Manager NI South Africa

Seminar Overview

• Data Logging with National Instruments.• Machine Condition Monitoring.• Electrical Power Monitoring.• Structural Monitoring

Data-logging Application Elements

Data Logging Defined

•Using an electronic instrument to take measurements from sensors and storing them for future use

•Common measurements: temperature, pressure, current, velocity, strain, displacement, etc.

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Flexibility

Sim

plic

itySimplicity vs. Flexibility

PC-Based

Stand-alone

PC-Based Data Logger

Traditional Stand-alone Data Loggers

Processor

RAM

ROM

Display

PowerSupply

Hard Disk

What is PC-Based Data Logging?

PC-Based Data Logging Checklist

• Simple configuration and PC connectivity• Easy-to-use data-logging software• Real-time data transfer• Online analysis & processing capability• Ability to add channels or measurement types• Scalable solution for future application needs

EASY

POWERFUL

OPEN

Flexibility

Sim

plic

itySimplicity vs. Flexibility

Simple & Flexible

Stand-alone

PC-Based

• EASY: Configuration-based software & true plug-and-play hardware

• POWERFUL: Online analysis & high-speed data streaming

• OPEN: Modular I/O & scalable software

EASY POWERFUL OPEN

• Easily log and analyze measurements without programming

• Quickly set up and configure data logging systems with plug and play USB technology

• Connect to 250+ DAQ devices, 400+ instruments and 1,000s of sensors

NEW! LabVIEW SignalExpress

What is LabVIEW SignalExpress?

Configuration-based logging & analysis software

What is LabVIEW SignalExpress?

Interactive, step-by-step data acquisition & configuration

What is LabVIEW SignalExpress?

Always-on, customizable views display live data & analysis

What is LabVIEW SignalExpress?Open in Microsoft Excel & email results

Stream data to disk

True Plug & Play USB Connectivity

Built-in Signal Conditioning

Over 30 Hot-swappable Modules

Built-in Signal Conditioning for

Sensors

What is CompactDAQ?Stream Data at

Over 5 MS/s

Data in Three Clicks

• True plug & play USB• Automatic detection &

configuration of hardware• Focus on measurements and

tests vs. hardware/software setup• Reduced setup time

1

2

3

DEMO: LabVIEW SignalExpress

• Simple configuration and PC connectivity

• Easy-to-use data-logging software

EASY POWERFUL OPEN

Online & Historical Data Analysis

EASY POWERFUL OPEN

•Built-in Analysis Functions– Signal processing– Time domain measurements– Frequency domain measurements– Statistics– Digital comparison and conversion– Many more…

Set Alarms & Configure Events

•Set custom conditions to start and stop logging–Start/Stop at specific date and time–Start/Stop based on data

•Customize alarm/event actions–Display messages–Set analog levels–Set digital lines–Audible alerts

Create Customized Reports

•Reports show live view of data•Drag and drop graphs and indicators•Enter free form text•Send to printer•Export to HTML

DEMO: Analysis & Reporting

• Online analysis & processing capability

• Real-time data transfer

EASY POWERFUL OPEN

I/O Capabilities in LabVIEW SignalExpress

• Analog Input• Analog Output• Static I/O • Counters• Correlated DIO• Synchronize Plug-In Boards

NI CompactDAQ Chassis Backplane

High-Speed Parallel Signal

Streaming

USB STC-2 Timing and Triggering

Module Auto-Detection

and Control

National Instruments USB Technology

Increased Device Intelligence• Module auto-detection & control• Device contains element of driver

92119215

9263

92339237

DAQmx

947294819472

9215

Relays ADCData to PC at

1.8 MB/s (GPIB)<500 S/s

DMM-Based Systems

ADC

ADCADCADC

Over 5 MS/s Timing & Bus

Controller (USB-STC2)

Data to and from PC at 60 MB/s

(USB 2.0)

NI CompactDAQ

ADCADCADCADC

Simultaneous, Multi-ADC System

USB

Input

Buffer

PC

Processor

USB Bus

USB

USBController

Output

USB Multi-Stream with NI Signal Streaming Technology

DEMO: NI Signal Streaming

• Online analysis & processing capability

• Real-time data transfer

EASY POWERFUL OPEN

Breadth of Measurements: I/O Modules

• Over 30 I/O modules available• Up to 256 analog/digital mixed channel count• Custom channel count &sensor support per system with

4ch to 32ch modules available• Compatible with 1000’s of

sensors

EASY POWERFUL OPEN

Signal to Backplane Isolation barrier

Safety, noise immunity,common mode rejection

Built-in Signal ConditioningDirect connection to

industrial sensors and actuators

Available 24-bit Delta-Sigma ADC

DSA signals, TEDS enabled,built-in antialiasing filters

Guaranteed AccuracyNIST traceable calibration

Integrated DAQ, Signal Conditioning & Connectivity

Isolation for Improved Accuracy & Safety

• Avoid ground loops• Protect System and user • Measure small signals on

a large potential

Digital Isolation

NEW! Isolated Modules

• 24-bit, ch-ch isolated, 50kS/s/ch• 9229 = ±60 VDC• 9239 = ±10 VDC• Screw Terminals• Industry standard certifications

Broad Sensor Compatibility• Thermocouples• RTDs• Thermistors• Strain gauges• Photo sensors

• Potentiometers• Load Cells• Optical Encoders• Microphones• Accelerometers

• pH electrodes• Headmeters• Flowmeters• Pressure gauges• Many more…

• 24-bit 100S/s/ch• Ch-ch isolated• 11 measurement modes

– Thermocouple (with 1 CJC per channel)– RTD (3 and 4 wire)– Resistance– Current– Digital– Voltage up to ±60V– ¼, ½, and full bridge strain with built in

excitation up to 2.7V

NEW! Universal Module (9219)

Flexible & Scalable Data Logging•Scale your applications with automatic code generation•Add additional functionality

– Custom user interface– Decision making– Additional analysis

•Add new hardware

DEMO: Scalability

• Ability to add channels or measurement types

• Scalable solution for future application needs

EASY POWERFUL OPEN

Diversity of Data-Logging Applications

Benchtop Industrial In-Vehicle

Benchtop Instrumentation• Measurements

– Verify circuit prototypes– Characterize components– Troubleshooting circuits

• Requirements– Fast time to measurement– Direct connectivity & benchtop accessories– Small size (25 x 6 x 9cm)– Standard time and frequency domain analysis– Reporting

• High-Voltage Isolation • Integrated signal conditioning• NI-DAQmx built-in OPC Server• High-speed data transfer• Rack mount and panel mount

accessories

Industrial Data Acquisition and Control

Halliburton Ultrasonic Cement Analyzer

“The small size of NI CompactDAQ helped us minimize the footprint of the analyzer, and the modularity of the platform gives us the ability to incorporate additional measurement types for special deployment requirements.”- Rick Bradshaw, Technical Professional Leader, R&D

Halliburton

In-Vehicle Data Acquisition

• DC Power • Lightweight, portable • Measurement support for

– Suspension– Fuel system– Comfort control– Brakes– Many more…

Honda In-Vehicle Suspension Test

“This system will revolutionize in-vehicle data acquisition for us. With the CompactDAQ system, we effectively transform a myriad of wires and equipment into a smaller, cleaner, cheaper and more intuitive package."

- Mike Dickinson, Transmission Research Engineer, Honda R&D Americas

Summary

• Data Logging defined• LabVIEW SignalExpress & CompactDAQ

– Easy: Configuration-based software and plug & play hardware– Powerful: Online analysis and high-speed data streaming– Open: Modular hardware and scalable software

• Diversity of Applications

(reactive) (active)

Maintenance Strategies

Issues addressed by machine monitoring:• Safety• Uptime (reliability, equipment effectiveness)• Quality

Lead Time of Options – What to Monitor

Time

Conditions start to change

Vibrations Noise

Heat

Smoke

Emergency stop

3 month

2 weeks2 days

10 min

Mac

hine

con

ditio

n

Courtesy of FAG Industrial Services

Vibration Sources- Where to Monitor

Slot Frequency / EM related

Motor

Couplings

Gears

Journal (Fluid Film) Bearings

Blade Pass / Fluid Related

Rolling ElementBearings

AlignmentUnbalance

MechanicalResonances

Bent ShaftLoose Mechanical

Components

Typical Sensing Data – A real machineGas Turbine4 Accelerometer4 Bearing RTD1 Gas Generator Speed1 Power Turbine Speed1 Fuel Flow1 Ambient Temperature1 Compressor Discharge Pressure1 Compressor Discharge Temperature1 Exhaust Gas Temperature1 Power Turbine Exhaust Temperature1 Power Turbine Exhaust Pressure1 Air Mass Flow4 Lube Oil Level Temp, Pressure,Level

Compressor4 Radial Vibration Proximeter Probe2 Axial Positioner4 RTD1 Suction Pressure1 Discharge Pressure1 Flow1 Inlet Temperature1 Discharge Temperature

Gearbox8 Radial Vibration Proximeter Probe2 Axial Positioner6 Bearing RTD1 High Speed Keyphasor1 Low Speed Keyphasor1 Gearbox Accelerometer

Courtesy Dresser-Rand Corporation

Typical Spectrum Showing Basic Faults

0.0

001

0.0

01

0.0

1

misalignment

unbalance

bearing frequencies

Frequency (Hz)100 1000 10000 100000

Velo

city

(ip

s)

gear mesh frequencies

Courtesy of

NI Advantages: Advanced Measurements, Advanced Analysis

Who Uses Condition Monitoring?• Power Generation

– Turbines (Gas, Steam, Hydro, Wind)– Boilers, pumps, motor

• Oil, Gas, PetroChem– Pumps, Compressors, expanders,

motor, fans• Pipelines

– Compressor, Pumps, piping, motor• Paper

– Rolllers, Press, Printing, pulp refiner, motor, fans

• Water– Pumps, Compressor, motor

• Food & Pharmaceuticals– Mixer, Pumps, Blowers, Fans, vessel,

boiler, centrifuge• Marine Propulsion

– Turbochargers, Gearbox, Bearings, motor

• Metals and Mining– Kilns, crusher, pulverizer

• Semiconductor– HVAC, Electrical Power, motor

Who Can Use Machine Monitoring?

• Rotating Equipment Engineer• Maintenance (Superintendent, Technician, Mgr)• Machinery Engineer• Reliability Engineer• Facilities Engineer• HVAC Engineer• Manufacturing Manager

Nexjen Reactor Pump Vibration Monitor• Challenge

– Provide a combined system for 32 vibration channels in four machinery locations

• NI Tools– PXI-DSA, LabVIEW, – S&V Measurement Suite

• Results– Real-Time Monitoring– Historical Data – Transient Data– Alarming– Expands to Process Variables

Previous Hoover Dam Solution

• 400 Lbs.• Dedicated

Instruments• Weak PC Integration

vibDaq Solution• 20 Lbs.• Virtual Instruments• PC based solution• www.vibdaq.com

Polar Plot Tabular ListOrbit Plot

Waterfall Plot

Cascade Plot

Run-Up

USB Machine DiagnosticsPortable Machinery Test and Condition Monitoring

NI CompactDAQ

NI USB-9233

Standard Plug-and-play USB 2.0 Alias-free, simultaneous, 24-bit A/Ds Time waveform, spectrum, and order analysisNonstandard Price… 4-channel USB-9233 + NI Sound and Vibration Assistant < $3,600

Remote Monitoring Interface

Simple Web Interface Pemex Compressor AppBy Instituto de Investigationes Electric

Demo Sound and Vibration

Problems and Focus on Bearing

Varnishing - overheating due to metal to metal contact

Scoring of thrust bearings: shock loading contamination

Effects of Bearing Failure

Impeller – Contact with casing and diffuser vanes

Bent Diffuser Vanes

Bending failure of gear teeth- seized rotor

Machine Monitoring Benefits

NI CompactRIO is ideal for machine monitoring

Real-Time ControllerLabVIEW RT

Reconfigurable RIO ChassisLabVIEW FPGA

I/O

Mod

ule

I/O

Mod

ule

I/O

Mod

ule

I/O

Mod

ule

I/O

Mod

ule

I/O

Mod

ule

I/O

Mod

ule

I/O

Mod

ule

CompactRIO Block Diagram

Ethernet RS-232

− C Series I/O Modules− Real-Time Controllers− RIO Backplanes

Connectivity ADCSignal Conditioning

Case Study: FAG Industrial Services (FIS) • FAG ProCheck - simple, intelligent, reliable

• FAG ProCheck is an intelligent online monitoring system of the latest generation that can measure, record and analyze data independently from other systems. Thanks to its very flexible configuration options, it can be used to monitor machines and components in nearly all industry sectors.

• Herzogenrath, April 16, 2007. In April 2007, FAG Industrial Services GmbH (F’IS) announced FAG ProCheck, a new powerful and flexible condition monitoring system for preventing unexpected production disruptions. The system stands alone in the marketplace by integrating the National Instruments CompactRIO hardware platform with the proven F’IS Administrator software to offer the right list of functions at an attractive price. “Because the system, based on CompactRIO, breaks so many of the previous boundaries for machine condition monitoring, we foresee it playing an important role in the future of the industry,” said Preston Johnson, NI Segment Manager, Sound and Vibration.

• http://www.fis-services.com/site/en

ISDN- phone

Satellite

Mobile phone

Internet

FIS Diagnosis-Center

Remote Service

Customer benefit:

• Automatic monitoring and early warning

• Recommendation for action by a trained analyst

Summary• National Instruments provides

– Machine Monitoring Solutions • Sound and Vibration Assistant, Partners

– OEM Components for Equipment Manufacturers– Measurement technology partner– Economies of scale

• Machine Monitoring – Saves time and money– Improves operational reliability

• Bring on the opps (MCM, POWER, STRUCT, NVH)

Machine and System OptimizationCase Studies

Case Study: Enginuity LLC• Leading supplier of emissions reduction

equipment in the oil and gas industry • Engineer and install advanced

combustion control technology for direct-injected, natural gas-fired industrial engines

• New controllers also monitor condition of engines

• Green Benefit:– Reduced over 22,000 tons of NOx

emissions with equipment tested and developed using NI technology

Testing New Controllers

• Large, older diesel engines are extremely expensive and unpredictable with how they will react to new controllers

• Retrofit technology must be tested and validated before being deployed on engines

• Enginuity used LabVIEW and PXI to simulate the engine inputs and outputs for their iFLEX engine monitoring and control system

Case Study: Nucor Steel Corporation

• One of the largest steel producers in the US, and the largest recycler

• Used LabVIEW and NI PACs to optimize their Marion, Ohio plant

• Implemented 3 automation systems to greatly increase efficiency and safety

• Green Benefits– Prevented the over-melting of scrap steel,

which wastes electricity, and requires re-heats due to poor quality

– Limits maximum power draw from city grid, avoiding costly penalties, and associated flicker and quality issues

Nucor Scale and Weighing System

• Accurately measures the amount of scrap steel to be melted in the furnace

• Calculates the exact amount of electricity needed to heat the steel

• Connects to existing machinery to communicate this information

• Monitors real-time power consumption from city grid

• Performs power quality analysis on measured data

• Connects to existing machinery to insure consumption does not exceed regulated limits

Nucor Power Monitoring Station

“Once you start monitoring something in an automation system, you know you can fix things”

- Dave Brandt Electrical Engineer

Enabling Technologies

• Power Monitoring• Power Quality Analysis• Connectivity to PLCs and Existing Systems

Power Quality Monitoring

What Is Power Quality?

• Power Quality– The quality of the Voltage & current that is being

supplied to any device• Requirements

– The waveform of the voltage and current should be as sinusoidal as possible

– Constant RMS/Frequency– There should be no transient features in the supply

Why Monitor Power?

• Machine fault detection• Eliminate monetary fines from power company• Manage generator/battery backups• Troubleshoot equipment

Power Chain

Generation DoorstopTransmission Distribution Machines

NI 9225

• CompactRIO and CompactDAQ• 3ch, 300V, 50kS/s, 24-bit• Same family as 9229/9239• Ch-Ch isolation

SensorsCurrent Transformers/Transducers• Waveform• RMS• AC/DC

Analysis of Electrical Power

• Harmonics • Voltage fluctuation

– Sag(or “dip”)– Swell

• Metering– Demand Side Management

• Power Factor

Voltage Sag

10% < RMS Voltage < 100%

Voltage Swell

110% < RMS Voltage

Voltage Interruption

RMS Voltage < 10%

Power TriangleRequire only V and I measurements

Reactive

Power [VAr]werApparentPo

alPowerPF

Re

(phi)

)cos(*Re IValPower

IVwerApparentPo *[VA]

[Watts]

PQ Events as categorized by

IEEE

Current Transformer

Competition

NI VAR/Alliance member National Instruments• Research Instruments• SBC

“Next Generation Power Meter”

• Ethernet and Internet connectivity• Open and standard communication protocol support• High-speed transient sampling• Statistical analysis for trending• Electronic notification of alarms• Memory for data storage• General Purpose User Interface

Frost & Sullivan: Power Quality Meters – Next Generation” Jan 9, 2007

NI Platform Advantages

Power Quality 3rd Party Recourses

• LEM sensors• CR Magnetics sensors• Elcom

Why Monitor Power?

• Power monitoring power can be important whether being consumed or generated– Protect expensive machines and equipment from failure

or excessive wear– Eliminate monetary fines from power company

• Poor power quality on your grid is subject to fines– Manage generator/battery backups– Troubleshoot equipment– Minimize energy waste

Why Monitor Power?

Power Quality Analysis

• Common analysis functions performed in power monitoring systems

• Defined by IEEE and derived from current and voltage waveform data– Harmonics/Frequency– Voltage fluctuation

• Sag• Swell• Interruption

– Metering• Demand Side Management

– Power Triangle

PQ Events as categorized by

IEEE

Harmonics/Frequency

Voltage Sag

10% < RMS Voltage < 90%

Voltage Swell

110% < RMS Voltage

Voltage Interruption

RMS Voltage < 10%

Power TriangleRequire only V and I measurements

Reactive

Power [VAr]werApparentPo

alPowerPF

Re

(phi)

)cos(*Re IValPower

IVwerApparentPo *[VA]

[Watts]

SensorsCurrent Transformers/Transducers

• Waveform• RMS• AC/DC• PF calculation with RS-

485 output• Industrially rated

Power Quality Summary

• Monitoring energy plays a key role in running an energy efficient machine, plant, or process

• Power quality can effect durability of equipment

• All power measurements stem from voltage and current waveform data

Structural Health Monitoring• Continuous monitoring of the condition of a structure using built-in or

autonomous sensory systems• Assess structural performance• Assess structural integrity following incident (earthquake)• Feedback loop in design (verify models, new materials, etc.)

The SHM Market in the U.S.•Aging infrastructure

– >590,000 bridges in U.S. (half were built before 1964)– 74,000 bridges are ‘structurally deficient’– American Society of Civil Engineers (ASCE) estimates that

it would take $9B/year for 20 years to eliminate bridge deficiencies

•Significant funding and research•Automated monitoring of infrastructure now readily available

Donghai Bridge - Structural Health Monitoring with PXI

Bridge Requirements• 20-mile long, operating

in harsh conditions• Long-term vibration

monitoring with low-maintenance

• High-level software to manage, analyze, and report on entire scale

Structural Health Monitoring of the Donghai Bridge with NI LabVIEW and PXI

Solution• 14 PXI systems

synchronized over GPS

• Continuous 24x7 operation for over 2-years

Rion-Antirion Bridge – Structural Monitoring

Bridge Requirements• 3 km bridge spanning the Corinth

Strait in Greece• Area of high seismic activity and

strong winds• High-channel, mixed sensor

measurements

Solution• Four PXI/SCXI systems• LabVIEW and LabVIEW Real-

Time• System integrator: Advitam,

subsidiary of Vinci Construction

Structural Health Monitoring of the Rion-Antirion Bridge

Beijing Olympic Venues - Seismic Monitoring and Research

• Continuously monitoring of seismic activity at the Beijing National Stadium and Aquatics Center– Structural model validation– Monitoring trigger events– Email notification

• NI LabVIEW and CompactRIO synchronized via GPS

. .

.Kinemetrics Seismic Sensors

cRIO

Vibration Monitoring of Meazza Stadium in Milan

Requirements• High-channel, distributed network

monitoring system• Structural evaluations, modal

analysis, static and dynamic measurements, and corrosion testing

Solution• 14 CompactRIO chassis with mixed

sensor connectivity• LabVIEW for flexibility and

advanced analysis Meazza Stadium Vibration Monitoring

Naini-Allahabad Bridge – Cable Stayed Bridge in India

• 500 monitored parameters– Strain (vibrating wire),

displacement, environment, GPS position

• 7 FieldPoint systems with LabVIEW RT

• Continuous monitoring – High speed burst mode when

threshold exceeded for vibration, wind, or GPS data

Smart Bridge ResearchTestbed – UCSD Powell Laboratory

HBM: Optical Technology for SHM

Optical Strain Gages

− Great number of optical SG per fiber− Light weight− Insensitive to electromagnetic interference− For use in potentially explosive atmospheres− Installation similar to electrical strain gages (SG)

Opto-electric Measurement Instrument

− Static: one to four channels, 1 to 5 S/s− Dynamic: one to four channels, 100 to 1000 S/s

Software

− catman® add-on module− Parallel recording of data from optical and conventional strain gage amplifiers− Real-time temperature compensation

Strain Measurements in SHM

Resistive Foil

Vibrating Wire

Fiber Optic

Measures voltage across changing resistance of foil

Measures change in frequency of light reflected

Measures change in resonant frequency of wire

NI 9237• 4-ch full/half-bridge inputs

– accessory for quarter-bridge• 50 kS/s• 100 dB dynamic range• Shunt cal, remote sense• Smart sensor (TEDS)

compatible

C Series Strain Measurements• 4 or 8 gauges per module, simultaneously sampled• Full, half, and quarter-bridge measurements• 24-bit resolution• ADC per channel, simultaneously sampled• Anti-aliasing filtering• NIST-traceable calibration

NI 9235, NI 9236 • 8-ch quarter-bridge inputs• 120Ω (9235) and 350Ω (9236)• 10kS/s per channel• 100 dB dynamic range

NI 9219• 4-ch universal inputs, including

quarter/half/full bridge inputs• 100 S/s • Smart sensor (TEDS)

compatible

Strain Measurements in SHM

Resistive Foil

Vibrating Wire

Fiber Optic

Measures voltage across changing resistance of foil

Measures change in frequency of light reflected

Measures change in resonant frequency of wire

Vibrating Wire Sensor Technology

• Frequency-based measurement and excitation of embedded steel wire under tension

• Compares to nominal resonant frequency• Surface mount on steel or concrete,

embedment in concrete or rebar• Typically 50 to 250 mm in length• Not intended for dynamic or rapidly changing

strain

Overview of Vibrating Wire

Surface of Component Being Tested

Hermetically Sealed Stainless Steel Body

Vibrating Steel Wire

Electromagnetic Coil Assembly- Excites and measures wire- Measures temp with thermistor

Sensor Cable

Mounting Block

3rd Party VW Signal Conditioners

• Amplification and signal conditioning for vibrating wire and thermistor

• Often 1 to 4 channel with easy expansion through multiplexer (16 or 32 channel)

• For use with pressure, load, strain, and temperature

Vibrating Wire Sensors

Pros• Immunity to noisy

environments• Frequency transmits well

over long distances• Stable over long periods

of time• Surface mount or embed

Cons• Long operation periods

delay reading• Not for dynamic

measurements

Fiber Optic Sensors

Λ

Grating Period

Input Light Reflected Light

Transmitted Light

λ

B

Fiber Bragg Grating(FBG)

Strain changes the frequency of light reflected by the FBG

Fiber Bragg Grating Sensor Interface HW

Prime Photonics

HBM

Smart Fibres

Micron Optics

Micron Optics

Gavea Sensors

FiberSensing

FiberSensing

Fiber Optic Bragg Grating Sensors

Pros• Multipoint in-line

measurement capability• Easy to integrate in hard

to reach areas• High sensitivity• Small / lightweight• Linear response

Cons• Sensitive to more than

one parameter• Cost of sensors• Require expensive

processing equipment

Distributed Measurement Synchronization

• Structural signals of interest are typically ≤10 Hz–cRIO, cDAQ, and PXI deliver synchronized solutions

• Two general classes of synchronization strategy:– Signal-Based

• Clocks and triggers physically connected between systems• Highest-precision synchronization

– Time-Based• System components have a common reference of what time it is• Events, Triggers and Clocks can be generated based on this time• Examples: NTP, IEEE 1588, and GPS

Comparing Synchronization Technologies

PXI Multichassis

NTP

GPS IEEE-1588

TCP/IP Messages

10-12 sec

On-chipPrecision

sec

10-3 sec

10-6 sec

10-9 sec

10-2m 100mProximity

101m 102m 103m 104m 105m Global<10-4m

Signal-Based

Time-Based

IRIG-B

Backplane

Distributed Synchronization Capabilities

10 Hz 100 Hz 1 kHz

0.1 deg

10 deg

1 deg

10 kHz1 Hz

Signal Bandwidth

Ch

-Ch

Ph

ase

Mis

mat

ch

CompactRIO

NTP

PXI

CompactRIO w/923x modules

Signal-Based

Time-Based

GPS IEEE-1588 Ethernet NTP Ethernet

CompactRIO

PXI

Structural Monitoring

• Plot represents conservative approximations• Many application-specific variables

Distributed Synchronization with CompactRIO

Signal-Based Synchronization• Share sample clock and start trigger• Similar approach: generate IRIG-B signal

and share time reference• For longer distances (> few meters),

transmit trigger (not high freq clock)• 9401/2 modules for timing signal I/O

– New: 9402 20MHz TTL with BNC (Mar ‘08)

Synchronization via GPS• GPS receiver – external or C Series• Two signaling options

– Pulse-per-second (PPS) to DIO module (9401/2), accompanied with serial read of absolute time

– IRIG-B signal to DIO module (9401/2)

• 9401/2 modules for connection to GPS receiver

External GPS

Receiver

FPGART

940x

92xx

92xx

92xx

FPGART

940x

92xx

92xx

92xx

FPGART

940x

92xx

92xx

92xx

FPGART

940x

GPS

92xx

92xx

Clock/trigger signal(or IRIG-B)

PPS (or IRIG-B) S.E.A. Module

New: C Series High-Speed DIO for Timing/Triggering

NI 9402• 4 channel DIO with BNC • 3.3V TTL; 5V input tolerant • 2 mA/line current drive• Propagation delay < 20 ns

– for comparison, 9401 delay = 100 ns• Line configurable direction control • 20MHz target (w/ 3 m cable)

– Longer cables with lower frequency or trigger pulses

• cRIO and cDAQ• Shipping target: Mar/Apr 2008