instrumentation project 2011..temperature measuring system

8/2/2019 Instrumentation Project 2011..Temperature Measuring System

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TEMPERATURE MEASURING SYSTEM

IN LAVATORY OF BOEING 737 AIRCRAFT

Prepared for

PROF IR DR WAN KHAIRUDDIN WAN ALI

SMF 3242 AIRCRAFT INSTRUMENTATION

SEMESTER 1, SESSION 2011/2012

Prepared by

3-SMT

CHAI CHANG WEI AM090031

LEONG WEI LOCK AM090083

MUHAMMAD FAIZ BIN ZAKARIA AM090306

NORHIDAYAH BT MAT SANGITI AM090212

ZIAD BIN ABDUL AWAL AM090331

MOHD MUAZ BIN ROSLAN AM090146

DECEMBER 23, 2011

UNIVERSITI TEKNOLOGI MALAYSIA


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TABLE OF CONTENTS

Content Page

Table of Contents i

1.0 INTRODUCTION 1

1.1 Title 1

1.2 Background 1

1.3 Objectives 1

1.4 Problem Statement 1

2.0 SELECTION OF 15 LOCATIONS FOR TEMPERATURE SENSORS 2

3.0 INTRODUCTION OF DATA ACQUISITION 4

4.0 SELECTION OF THERMAL TRANSDUCER 5

4.1 2 Wire Space Air Thermistor Temperature 5

4.2 Thermistor Extension Wire 7

5.0 SIGNAL CONDITIONING SYSTEM 8

5.1 Terminal Block 8

5.2 Module 10

5.3 Chassis 12

5.4 Shielded Cable Assemblies 13

6.0 DAQ HARDWARE 16

7.0 DAQ SOFTWARE 18

7.1 Programming algorithm

7.2 Software Flow Chart 19

8.0 WIRING

20

9.0 COST CALCULATION 22

10.0 CONCLUSION 22

APPENDIX 23


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1.0 INTRODUCTION

1.1 Title

Design of temperature measuring system in lavatory of Boeing 737 aircraft.

1.2 Background

An aircraft lavatory is an onboard bathroom with a toilet and sink. The first toilets in airplanes

were simple buckets. Information on early flushing systems is not available, however aircraft's

cabins were not pressurized and it was easy to open doors and windows.

The classical type lavatory is mainly seen in aircraft manufactured before the mid 80's and offers

passengers a reasonable comfort and flush plentifully. Applying a layer of toilet paper on the

stainless steel bowl, before use, guaranty a good wash with a single flush. The conventional,

none confusing, flush handle is used correctly by all passengers.

Nowadays, in order to provide an extra comfort for the passengers during onboard, a conditioned

air is introduced in the cabin washroom. Some temperature measuring system that is contact

sensor has to be put in the lavatory so that the user feels comfortable. Contact temperature

sensors measure their own temperature. One infers the temperature of the object to which the

sensor is in contact by assuming or knowing that the two are in thermal equilibrium, that is, there

is no heat flow between them.

1.3 Objectives

1. To provide an extra comfort for the passengers.2. To design temperature measuring system.3. To measure temperature at 15 locations in the cabin washroom by using off-the-shelf

components.

1.4 Problem Statement

Regulation of air temperature in the washroom is imperative to provide thermal comfort for

passengers, particularly at facial region as cheek tissues are sensitive towards temperature

changes. In this project, we will locate 15 appropriate spots in the lavatory of Boeing 737 aircraft

to install temperature sensors. Furthermore, the research team will design a PC-based data

acquisition system, consisting of signal conditioning, data acquisition hardware and software, to

analyze air temperature within the washroom.
http://en.wikipedia.org/wiki/Bathroomhttp://en.wikipedia.org/wiki/Bathroom


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2.0 SELECTION OF 15 LOCATIONS FOR TEMPERATURE SENSORS

Human cheek is able to detect deviations of temperature up to 0.5 degree Celsius per second and

is usually exposed. Due to its high sensitivity, humans thermal comfort mainly depends on

cheek comfort, in an air conditioned room. Hence, air temperature monitoring system in aircraft

lavatory generally focuses on human cheek surface temperature.

A passenger walks in the lavatory and carries out personal activities such as urinating (male),

shaving, applying make-up, brushing teeth and etc. in standing position. In order to monitor air

temperature at the cheek regions while the passenger is standing, 3 sensors are installed in the

front, left and right walls respectively at an average height of 1.70m for male and 1.58m for

female.

In the case where the passenger uses the toilet bowl in sitting position, the air temperature at

facial region is monitored by installing sensors in the left and right walls at an average height of1.22m for male and 1.10m for female. Sensor will not be installed in the front wall at this

position as the back of the head is usually covered with hair, thus causing the sensitivity of the

scalp towards small temperature changes becomes insignificant.

Other than facial region, other exposed body parts

such as limbs and neck also contribute in thermal

comfort. Here, we consider only at sitting position.

Thus, a sensor is placed behind the neck area at

height of 1.17m for male and 1.05m for female. To

detect air temperature changes at hands, 2 sensorsare located at the left and right wall at height of

0.45m, assuming that the passengers hands will be

resting on his/her lap. Lastly, a single monitoring

point is installed at the calf level to detect changes in

air temperature at the surrounding of legs.

Figure 1 3D view of lavatory in B737


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Figure 2 Locations of 15 Temperature Sensors


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3.0 INTRODUCTION OF DATA ACQUISITION

Data acquisition (DAQ) is the process of measuring an electrical or physical phenomenon such

as voltage, current, temperature, pressure, or sound with a computer. A DAQ system consists of

sensors, DAQ measurement hardware, and a computer with programmable software. Compared

to traditional measurement systems, PC-based DAQ systems exploit the processing power,

productivity, display, and connectivity capabilities of industry-standard computers providing a

more powerful, flexible, and cost-effective measurement solution.

DAQ Devices

DAQ hardware acts as the interface between a computer and signals from the outside world. It

primarily functions as a device that digitizes incoming analog signals so that a computer can

interpret them. The three key components of a DAQ device used for measuring a signal are the

signal conditioning circuitry, analog-to-digital converter (ADC), and computer bus. Many DAQ

devices include other functions for automating measurement systems and processes. Forexample, digital-to-analog converters (DACs) output analog signals, digital I/O lines input and

output digital signals, and counter/timers count and generate digital pulses.

Figure 3 Components in DAQ system


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4.0 SELECTION OF THERMAL TRANSDUCER

A sensor (also called detector) is a device that measures a physical quantity and converts it into a

signal which can be read by an observer or by an instrument. A sensor's sensitivity indicates how

much the sensor's output changes when the measured quantity changes. Among many sensors,

thermal sensor is one of them. A temperature or thermal sensor is a type of sensor which is used

to measure temperature. There are various types of thermal sensors such as thermistor,

thermocouple, thermometer, RTDs etc. We have chosen thermistor for our project.

A thermistor is a type ofresistor whose resistance varies significantly with temperature, more so

than in standard resistors. A thermistor is a piece of semiconductor made from metal oxides,

pressed into a small bead, disk, wafer, or other shape, sintered at high temperatures, and finally

coated with epoxy or glass. The resulting device exhibits an electrical resistance that varies with

temperature. There are two types of thermistorsnegative temperature coefficient (NTC)

thermistors, whose resistance decreases with increasing temperature, and positive temperature

coefficient (PTC) thermistors, whose resistance increases with increasing temperature

Advantages of thermistor:

1. extremely high sensitivity2. fast response to temperature changes (small size of the thermistor bead)3. relatively inexpensive4. relatively high resistance

Disadvantages:

1. Highly nonlinear output and relatively limited operating range.2. Fragile

4.1 2 Wire Space Air Thermistor Temperature

Refer APPENDIX A for thermistors specification

Attributes:

Attribute Type Attribute Value

Type Temperature, Thermistor

Voltage 0 to 10V dc

Dimensions 85x85x23mm

RS Stock No. 813-806

Manufacturer RS

Manufacturers Part No. TT911/10K3A1
http://en.wikipedia.org/wiki/Resistorhttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Temperaturehttp://en.wikipedia.org/wiki/Temperaturehttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Resistor


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Price

Quantity Unit Price

1 MYR59.40

12 MYR56.50

25 MYR54.20

Physical installation

RS stock no.813-806 Space air temp. Affix back plate to wall or back-box in a location

which excludes drafts and direct sunlight. Use terminal supplied for connecting to

sensor.

Electrical installation

1. Make electrical connections to sensor only after all other electrical installation and test has

been completed.

2. It is recommended that screened cable be used on all installation, with screens being earthed

at the controller. Signal cables should not be laid in close proximity to power cables or other

sources of interference.

3. Connections to the sensing element are non-polar.

4. Note: Thermistors exposed to excess voltage and/or current will usually fail closed

circuit. Units failing in this way will not be repaired or replaced under warranty.

Connecting the Thermistors:

The easiest way to connect a thermistor to a measurement device is with a two-wire connection

(Figure 3). With this method, the two wires that provide the thermistor with its excitation sourceare also used to measure the voltage across the sensor. Because thermistors have a high nominal

resistance, lead-wire resistance does not affect the accuracy of their measurements; thus, two-

wire measurements are adequate for thermistors, and two-wire thermistors are the most common.

Figure 4 Two-Wires Connection


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4.2 Thermistor Extension Wire:

(Nickel-Plated Copper Wire)

Color Code: 2 CuRd/Bk; 3 CuRd/Bk/Bk; 4 Cu-Rd/Rd/Bk/Bk

InsulationAWGNo.

ModelNumber

Price/1000'

# ofCon.

t.kg/300m(lb/1000')

Glass 20262626

EXGG-2CU-20EXGG-2CU-26SEXGG-3CU-26SEXGG-4CU-26S

$370280360420

2234

Solid7x347x347x34

GlassbraidGlassbraidGlassbraidGlassbraid

GlassbraidGlassbraidGlassbraidGlassbraid

482482482482

900900900900

1.5x2.4(0.060x0.095)1.5x1.3(0.060x0.052)1.5x1.6(0.060x0.064)1.5x1.7(0.060x0.066)

4(9)2(5)3(7)4(9)

NeoflonPFA

262626

EXTT-2CU-26SEXTT-3CU-26SEXTT-4CU-26S

480650700

234

7x347x347x34

PFAPFAPFA

PFAPFAPFA

260260260

500500500

1.1x1.7(0.042x0.068)1.8(0.072Dia.)2.1(0.082Dia.)

2(5)4(9)4(9)

Polyvinyl 2424

EXPP-2CU-24SEXPP-3CU-24S

390520

23

7x327x32 PolyvinylPolyvinyl PolyvinylPolyvinyl 105105 221221 2.1x3.4(0.082x0.134)4.22(0.166Dia.) 5(10)6(14)

Maximum temperature is for extension-grade wire or insulation, whichever is lower. Weight of spool and wire rounded to the next highest kg/lb Can be welded. Can also be red/gray.


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5.0 SIGNAL CONDITIONING SYSTEM

The use of thermistors for temperature measurement with a PC-based DAQ system requires

some signal conditioning as shown as above diagram. Signal conditioning is defined here as any

conditioning required to interface the thermistor and its output signal to a DAQ board or module.

Briefly, signal conditioning for thermistors should include the following functionality such as

excitation current or voltage source, signal amplification, lowpass filtering, isolation and

multiplexing. Components selected in this signal conditioning system:

1. Terminal Block: NI SCXI-13222. Module: NI SCXI-11223. Chassis: NI SCXI-10004. Cable assembly: SCXI-1349 Adapter and SH68-68-EP Cables

5.1 Terminal Block

Refer to APPENDIX B for the specification of this product

The NI SCXI-1322 front-mount terminal blocks feature direct connections to transducers at thescrew terminals located within a fully shielded enclosure or at front-mounted BNC connectors.

Strain-relief clamps hold the signal wires safely in place.

Features:

Terminal blocks for quick, easy connections

Strain-relief clamps for reliable wiring

Shielded front-mount terminal blocks

Rack and DIN-rail mount options available

Terminal block options for specific measurement types

Onboard temperature sensor for cold-junction compensation

High-voltage attenuation

Bridge offset nulling, shunt calibration

Product NI SCXI-1322

Part Number 777687-2

Manufacturer National Instruments

Description SCXI-1322 Temperature Sensor Terminal

Block

Price MYR 784.00


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Signal Connections

To connect the signal to the terminal block, perform the following steps, referring to Figures 5

and 6 as necessary:

1. Unscrew the top cover screws and remove the cover.2. Loosen the strain-relief screws and remove the strain-relief bar.3. Run the signal wires through the strain-relief opening.

4. Prepare your signal wire by stripping the insulation no more than7 mm.

5. Connect the wires to the screw terminals by inserting the stripped end of the wire fully

into the terminal. No bare wire should extend past the screw terminal.

6. Tighten the screws to a torque of 57 in.-lb.

7. Connect safety earth ground to the safety-ground solder lug.

8. Reinstall the strain-relief bar and tighten the strain-relief screws.

9. Reinstall the top cover and tighten the top cover screws.

10. Connect the terminal block to the module front connector.

Figure 5 SCXI-1322 Parts Locator Diagram

Figure 6 SCXI-1322 Signal Connections


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To connect the terminal block to the SCXI module front connector, perform the following steps:

1. Connect the module front connector to its mating connector on the terminal block.

2. Tighten the top and bottom thumbscrews on the back of the terminal block.

5.2 Module

Refer to APPENDIX C for the specification of this product

The SCXI-1122 is well suited for thermistors. The SCXI-1121 is an isolated amplifier andmultiplexer module with four isolated input channels. Each of the four channels has an amplifier

with jumper-selectable gain (from 1 to 2,000) and a low pass filter (4 Hz or 10 kHz). The SCXI-

1121 also has four channels of isolated voltage or current excitation. The SCXI-1122 is

multiplexer input module that can be configured for 16 two-wire inputs or 8 four-wire thermistor

inputs. The inputs are multiplexed into one isolation amplifier, which is programmable for a gain

of 0.01 (for high voltages) to 2,000. The module includes one isolated voltage and one isolated

current source.

Figure 7 SCXI-1122 Parts Locator Diagram




Description SCXI-1122 16-Channel Isolated Transducer Multiplexer

Price MYR 5,545.00


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Figure 8 Front Signal Connector Figure 9 Rear Signal Connector

The descriptions for front and rear signal connection in Figure 8 and Figure 9 are shown in

APPENDIX F

Figure 10 SCXI-1122 Block Diagram


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Installation steps:

1. Turn off the computer that contains the DAQ board or disconnect it from your SCXI chassis.

2. Turn off the SCXI chassis. Do not insert the SCXI-1122 into a chassis that is turned on.

3. Insert the SCXI-1122 into the module guides. Gently guide the module into the back of the

slot until the connectors make good contact.

4. Turn on the SCXI chassis.

5. Turn on the computer or reconnect it to your chassis.

5.3 Chassis

Refer to APPENDIX D for the specification of this product

The NI SCXI-1000 is a 4-slot chassis available with a number of standard AC power options.

This chassis is ideal for single-chassis or low-channel-count applications. If your application

grows, you can daisy-chain two or more SCXI-1000 chassis. You can also use off-the-shelf true

sine wave DC-to-AC power inverters to power AC chassis with a DC power supply.

Features:

Shielded enclosures for SCXI modules Low-noise environment for signal conditioning Rugged, compact chassis Forced air cooling Optional USB data acquisition and control module Optional rack mounting 3 internal analog buses Timing circuitry for high-speed multiplexing NI-DAQmx driver software simplifies chassis configuration




Description SCXI-1000 4-Slot Chassis, United Kingdom,240 VAC

Price MYR 3,066.00


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Figure 11 SCXI-1000 Front View Diagram Figure 12 SCXI-1000 Rear View Diagram

Installation steps:

1. Power off the chassis.

2. Make sure the voltage selection tumbler in the power entry module is set for the line voltage

of the outlet.

3. Insert the female end of the power cord into the power entry module.

4. Insert the male end of the power cord into the wall outlet.

5. Install the modules into the chassis.

6. Install any front and rear filler panels.

7. Power on the chassis.

5.4 Shielded Cable Assemblies

Product SCXI-1349 Adapter



Description Bracket/Adapter Assembly, SCXI-1349

Price MYR 389.00


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Product SH68-68-EP Cables



Description SH68-68-EP, Shielded Cable, 2 m

Price MYR 440.00

Refer to APPENDIX E for specification of this product

NI SCXI cable assemblies connect a DAQ device to the SCXI system. They consist of high-

quality, low-noise cables, which guarantee reliable communication and signal integrity at up to

10 m. Therefore, you can locate your SCXI system closer to your sensors and transducers.

The SCXI-1349 connects any 68-pin E Series DAQ device, excluding 61XXE devices, to any

SCXI module, excluding SCXI switch modules.

The SCXI-1349 is a connector assembly with three connectors:

A 68-pin male connector on the front panel of the adapter A 50-pin male breakout connector on the printed-circuit board of the adapter

A 50-pin bracket-mounted female connector on the rear of the adapter

Figure 13 SCXI-1349 Adapter Connectors Figure 14 SCXI-1349 Cable Assembly


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Figure 16 Complete SCXI System

Installation steps:

1. Turn the power off and unplug the SCXI chassis.

2. Install the SCXI modules into the chassis

3. Within the SCXI chassis, identify the appropriate SCXI module to connect to the cable adapter.

4. Insert the 50-pin female connection on the rear of the SCXI-1349 into the 50-pin male

connector on the rear of the appropriate SCXI module.5. Connect either end of the 68-pin shielded cable to the SCXI-1349 adapter.


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6.0 DAQ HARDWARE

Refer to APPENDIX G for the specification of this product

NI Full-Featured E Series devices are the fastest and the most accurate multiplexed data

acquisition devices available. They are ideal for applications ranging from continuous high-

speed data logging to control applications to high voltage signal or sensor measurements when

used with NI signal conditioning. Synchronize the operations of multiple devices using the RTSI

bus or PXI trigger bus and easily integrate other hardware such as motion control and machine

vision to create an entire measurement and control system.

Highly Accurate Hardware Design

The DAQ NI6070E comes with those features and technology:

1. Temperature Drift Protection CircuitryDesigned with components that minimize theeffect of temperature changes on measurements to less than 0.0006% of reading per C.

2. Resolution-Improvement TechnologiesCarefully designed noise floor maximizesresolution.

3. Onboard Self-Calibration Precise voltage reference included for calibration andmeasurement accuracy. Self-calibration is completely software controlled, with no

potentiometers to adjust.

4. NI DAQ-STCTiming and control ASIC designed to provide more flexibility, lowerpower consumption, and a higher immunity to noise and jitter than off-the-shelf

counter/timer chips.

5. OnBoard Temperature SensorIncluded for monitoring the operating temperature of thedevice to ensure that it is operating within the specified range.

6. Analog and Digital TriggeringOnly full-featured E Series devices provide the ability toset a trigger based on the level of an analog signal, in addition to the ability to trigger

off an edge of a digital signal

7. NI MITE ASIC designed to optimize data transfer for multiple simultaneousoperations using bus mastering with three scatter- gather DMA channels for

maximum performance of concurrent I/O operations.

Product NI PXI 6070E card



Price MYR 11079.00


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Figure 17 Block Diagram of NI DAQ 6070E Figure 18 Signal Connection Terminal

Refer APPENDIX H for the descriptions of each terminal shown in Figure 18


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7.0 DAQ SOFTWARE

By using LabVIEW, we can quickly and easily acquire real-world signals, perform analysis to

ascertain meaningful data, and communicate or store results in a variety of ways

Feature of the software:

Easy-to-use graphical development environment Tight integration with a wide range of measurement hardware Rapid user interface development for displaying live data Extensive signal processing, analysis, and math functionality Multiple communication options (TCP/IP, UDP, serial, and more) Support for Windows XP/Vista/7 (32-bit) and Windows Vista/7 (64-bit)

7.1 Programming algorithm

Selecting the Signal

1. The DAQ assistant opens a new window.2. Expand Acquire Signal, then expand Analog Input.3. Click on the Voltage icon.

- Selecting the Sensor Channel4. The temperature sensor is connected to channel 0, so select ai0 from the DAQ Assistant.5. Sensor Setup

Maximum voltage Vmax (corresponds to 100C)

Minimum voltage Vmin (corresponds to 0C)

Number of samples: 10 Sample Rate: 10 Hz

6. Create Conversion EquationRight click on the block diagram. Functions >> Programming >> Numeric out

7. Display the graph of temperature versus time

Product Software NI LabVIEW full development system for windows


Price MYR 9204.00


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7.2 Software Flow Chart

Begin

Data Input

Accquire

Measurement

Celsius?

Display

Tem erature

Voltage-temperature

(Celsius) conversion

End

Voltage-temperature (Fahrenheit)

conversion

( ) []+32


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8.0 WIRING

Figure 19 Wiring of DAQ in B737-200

19m

DAQ

Com uter

Chasis

IEEE cable

Shielded cable


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For B737-200 aircraft, the two lavatories were 29 m apart. The DAQ system for monitoring both

washrooms is located at the back of the aircraft beside the rear lavatory. The chain of

components ranging from thermistors, terminal block, and module to chassis is condensed in

each lavatory. Then, the digitized signals from both lavatories are channelled to a computer

positioned beside the rear lavatory via grounded IEEE cable across the cabin. The signals are

then analysed in Labview and displayed in desired manner. The total length of wires required to

connect DAQ from both lavatories to the computer is approximately 20 meters.

The IEE cable detail is as following:

Features

Up to 800 Mbps full-duplex bidirectional high speed data transmission. Multiple shielding and insulation for maximum speed without data loss. Developed for Low Emissions and High Immunity (automotive applications). Thin, flexible cable type. OD: 4 mm (vs 7-8 mm of regular Firewire-800 cables). RoHS compliant. AWG: 23 Min. Bend Radius (Install): 1.5in (3.81 cm) Temperature: -30' - 75' C (-22' - 167' F) Operating voltage: 12V

Product FireWire-800 (IEEE 1394b) 'smart' cables

Manufacturer Unibrain

Price 534.47 MYR for 20 metres


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9.0 COST CALCULATION

No. Item Price (MYR) Quantity Total (MYR)

1 Thermistor 54.20 25 1652.00

59.40 5

2 Terminal Block SCXI 1322 784.00 4 3136.003 Module SCXI 1122 5545.00 4 22180.00

4 Chassis SCXI-1000 3066.00 2 6132.00

5 Shielded cable SH68-68-EP 389.00 2 778.00

6 SCXI 1349 Adapter 440.00 2 880.00

7 DAQ PXI 6070E 11079.00 2 22158.00

8 Labview Software 9204.00 1 9204.00

9 Wiring IEEE Cable (20m) - - 534.00

10 Nickel Plated Copper Wire (20m) - - 701.32

11 Labour Cost - - 33677.66

TOTAL 101032.98

The total of RM 101 032.98 is meant for the temperature monitoring system for two lavatories in

B737 aircraft.

10.0 CONCLUSION

Aircraft lavatorys temperature sensing system had been designed and several off-shelf products

had been chosen to fit into our design. Thermistor (813-806,RS) is chosen as our designs

transducer, terminal block(SCXI-1322, National Instruments) ,Module (NI SCXI-1122, National

Instruments) and chassis(NI SCXI-1000, National Instruments) are selected as data conditioning

device, while DAQ (NI PXI 6070 E, National instruments) act as a ADC device in the designed

system. Shielded cable (SH68-68-EP, National Instruments) and Adapter (182671-01, National

Instruments) are used to connect DAQ and chassis. Lastly, the connection between DAQs

output is done by using IEEE wire (FireWire-800 (IEEE 1394b) 'smart' cables, Unibrain). The

overall price of the whole system is estimated to be RM 101 032.98.

References:

Kirianaki, N.V., Yurish, S.Y., Shpak, N.O., & Deynega, V.P. (2002).Data Acquisition and Signal

Processing for Smart Sensors. England: John Wiley & Sons.

Austerlitz, H. (2003). DataAcquisition Techniques Using PCs (2nd

ed.). USA: Elsevier Science.

James, K. (2000). PC Interfacing and Data Acquisition. Oxford: Newnes.

Taylor, H.R. (1997).Data Acquisition for Sensor Systems. London: Chapman & Hall.

National Instruments. Retrieved on December 10, 2011 from http://malaysia.ni.com/

Potter, D.Measuring Temperature with ThermistorA Tutorial. Retrieved December 10, 2011 from

http://www.noise.physx.u-szeged.hu/DigitalMeasurements/Sensors/Thermistors.pdf
http://malaysia.ni.com/http://www.noise.physx.u-szeged.hu/DigitalMeasurements/Sensors/Thermistors.pdfhttp://www.noise.physx.u-szeged.hu/DigitalMeasurements/Sensors/Thermistors.pdfhttp://malaysia.ni.com/


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APPENDIX A

Specification of Thermistor

Sensors contain a negative temperature co-efficient (NTC), curve- matched thermistor. The temperature/resistance

characteristic is given below:

Technical specification

Thermistor accuracy : 0.5C in the range 0-70C

Self heating effect Recommended : 1.0C/mW Recommended

Power rating :


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APPENDIX B

Specification of Terminal Block SCXI-1322

All specifications are typical at 25 C unless otherwise specified.

Cold-junction sensor

Accuracy........................................ 0.65 from 15 to 35 C

0.85 from 0 to 15 C and 35 to 55 C

Repeatability ................................... 0.4 from 15 to 35 C

Output ............................................. 1.91 to 0.58 V from 0 to 55 C

Common-mode isolation

Terminal to terminal ....................... 250 Vrms

Terminal to earth............................. 480 Vrms

Approved at altitudes up to 2000 meters.

Environment

Operating temperature ............................0 to 50 C

Storage temperature ................................20 to 70 C

Relative humidity ...................................5% to 90% noncondensing


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APPENDIX C

Specifications of Module NI SCXI-1122

Input CharacteristicsNumber of channels 16 differential, 8 4-wire, software selectable

Input signal ranges

Input coupling DC

Max working voltage Each input should remain within 480 Vrms of(signal + common mode) ground, and within 250 Vrms of any other channel

Overvoltage protection 250 Vrms powered on, 250 V powered off

Protected terminals CH < 0..15>, IEX+, IEX-, VEX+, VEX-

Transfer CharacteristicsNonlinearity 0.01% FSR

Offset error

Gain 1 (6 mV + 1,240 mV/gain)

Gain < 1 (352 mV + 1,240 mV/gain)

Gain error

Gain 1 0.02% of reading

Gain < 1 0.10% of reading

Amplifier CharacteristicsInput impedance

Normal powered on 1 GW in parallel with 100 pF for gain >1,

1 MW in parallel with 100 pF for gain < 1

Powered off 100 kW

Overload 100 kW

Input bias current 80 pA

Module Gain Max Module Range

10 V

0.01 250 VDC or

Vrms

0.02 250 V

0.05 200 V

0.1 100 V

0.2 50 V

0.5 20 V

1 10 V

2 5 V

5 2 V10 1 V

20 500 mV

50 200 mV

100 100 mV

200 50 mV

500 20 mV

1,000 10 mV

2,000 5 mV


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CMRR

Output range 10 V

Output impedance 75 W

Dynamic CharacteristicsBandwidth (-3 dB) 4 Hz (-10 dB) or 4 kHz, software selectable

Settling time to full-scale step (all gains)

with 4 kHz filter enabled 10 ms

with 4 kHz filter enabled 1 s

System noise

Slew rate 0.10 V/ms

FiltersType 3-pole RC

Cutoff frequency (-3 dB) 4 Hz (-10 dB) or 4 kHz, software selectable

NMR (50 or 60 Hz) 60 dB at 4 Hz bandwidth

StabilityRecommended warm-up time 20 minutes

Offset temperature coefficient (0.2 + 150/gain) mV/C

Gain temperature coefficient 10 ppm/C for gain 1, 25 ppm/C for gain < 1

Excitation

Output CharacteristicsChannels 2 (1 voltage and 1 current)

Bridge type Quarter, half, or fullBridge completion Two 2.5 kW 0.02% ratio tolerance resistors

Voltage ModeLevel 3.333 V 0.04%

Current drive 225 mA

Drift 30 ppm/C

Current ModeLevel 1.0 mA 0.04%

Max load resistance 5 kW

Drift 40 ppm/C

PhysicalDimensions 3.0 by 17.3 by 20.3 cm (1.2 by 6.8 by 8.0 in.)

I/O connectors 50-pin male ribbon cable rear connector

48-pin male DIN C front I/O connectorEnvironmentOperating temperature 0 to 50 C

Storage temperature -20 to 70 C

Relative humidity 10% to 90%

Maximum altitude


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APPENDIX D

Specifications of ChasisSCXI-1000

These are typical at 25 C unless otherwise stated.

Electrical Characteristics

Supplies SCXI-1000

V+

Tolerance limits include peaks +18.5 to +25 V

Ripple (peak-to-peak) 1.5 V

Max load 680 mA

V-

Tolerance limits include peaks -18.5 to -25 V

Ripple (peak-to-peak) 1.5 V

Max load 680 mA

+5V

Tolerance limits include peaks +4.75 to +5.25 V

Ripple (peak-to-peak) 50 mV

Max load

Power dissipation ................................... 7 W per slot

Maximum loads are the supply current for the entire chassis. Scaling the maximum power gives the allotted current

per slot, as follows.

Supplies SCXI-1000

V+ 170 mA

V 170 mA

+5 V +5 V


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APPENDIX E

Specifications of Shielded Cable SH68-68-EP

Source Power Requirements

For Line Voltage of240 VAC, 10%, 4763 Hz, maximum AC current is 0.25 A.

Environmental

Operating temperature 0 to 50 C

Storage temperature 20 to 70 C

Humidity 10 to 90% RH, noncondensing

Maximum altitude 2,000 meters

Pollution Degree (indoor use only) 2

Analog Input

Maximum working voltage 30 Vrms, 42 Vpk, 60 VDC

(signal + common-mode)

Environmental

Operating temperature 0 to 50 C

Storage temperature 20 to 70 C

Relative humidity 10 to 90% noncondensing


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APPENDIX F

Descriptions of Front and Rear Signal Connections for Module NI SCXI 1122

Front Signal Connection Descriptions

Pin Signal Name Description

A1 TEMP- Temperature Sensor ReferenceThis pin is tied to the temperature sensor reference in the terminalblock and to the isolation amplifier negative input in the module.

A3 TEMP+ Temperature Sensor OutputThis pin connects the temperature sensor output to the amplifier input

selector.

A7 +5 V +5 VDC Isolated SourceThis pin, which powers the temperature sensor on the terminal block, has

0.5 mA of source not protected.

A11 VEX/2 Half Voltage Excitation OutputThis pin connects to the internal bridge completion network for

quarter-bridge and half-bridge measurements. Protected to 20 V maximum.

A13 VEX- Negative Voltage Excitation OutputThis pin is connected to the voltage excitation negative output.

A15 SENSE- Negative Voltage SenseThis pin must be tied to VEX- at the load for remote sensing. When using

the SCXI-1322 terminal block, this pin is connected to VEX/SENSE screw terminals.

A17 SENSE+ Positive Voltage SenseThis pin must be tied to VEX+ at the load for remote sensing. When using

the SCXI-1322 terminal block, this pin is connected to VEX/SENSE+ screw terminals. This pin is

notprotectedA19 VEX+ Positive Voltage Excitation OutputThis pin is connected to the voltage excitation positive output.

A21 IEX- Negative Current Excitation OutputThis pin is connected to the current excitation negative output.

A23 IEX+ Positive Current Excitation OutputThis pin is connected to the current excitation positive output.

A5, A9,

A25-A29

No ConnectDo notconnect any signal to these pins.

A31 RSVD ReservedThis pin is reserved. Do not connect any signal to this pin.

B32-B2 CH+(0:15) Positive Input ChannelThese pins are connected to the positive input channels 0 through 15

respectively.

C31-C1 CH-(0:15) Negative Input ChannelThese pins are connected to the negative input channels 0 through 15

respectively.

Rear Signal Connection DescriptionPin Signal Name Description

1, 2 AOGND Analog Output GroundThese pins are connected to theanalog reference when jumper W1 is in position

AB-R0.

3, 4 Analog Output Channels 0Connects to the DAQ boarddifferential analog input channels.

19 OUTREF Output ReferenceThis pin serves as the reference node forthe analog channels output in the

pseudodifferentialreference mode. It should be connected to the analog inputsense of the NRSE DAQ

board.

24, 33 DIGGND Digital GroundThese pins supply the reference for DAQboard digital signals and are tied to the module

digitalground.

25 SERDATIN Serial Data InThis signal taps into the SCXIbus MOSI line to send serial input data to a module or Slot

0.

26 SERDATOUT Serial Data OutThis signal taps into the SCXIbus MISOline to accept serial output data from a module.

27 DAQD*/A DAQ Board Data/Address LineThis signal taps into theSCXIbus D*/A line to indicate to the modulewhether theincoming serial stream is data or address information

29 SLOT0SEL* Slot 0 SelectThis signal taps into the SCXIbus INTR* line to indicate whether the information on

MOSI is being sentto a module or Slot 0.

36 SCANCLK Scan ClockThis indicates to the SCXI-1122 that a samplehas been taken by the DAQ board and causes

theSCXI-1122 to change channels.

37 SERCLK Serial ClockThis signal taps into the SCXIbus SPICLK line to clock the data on the MOSI and MISO

lines.

43, 46 RSVD Reserved.

All other pins are not connected.


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APPENDIX G

NI6070E Specifications

General

Product Name PCI-6070E

Product Family Multifunction Data Acquisition

Form Factor PCI


Operating System/Target Real-Time , Linux , Mac OS , Windows

LabVIEW RT Support Yes

DAQ Product Family E Series

RoHS Compliant No

Analog Input

Channels 16 , 8

Single-Ended Channels 16

Differential Channels 8

Resolution 12 bits

Sample Rate 1.25 MS/sMax Voltage 10 V

Maximum Voltage Range -10 V , 10 V

Maximum Voltage Range Accuracy 14.369 mV

Minimum Voltage Range -50 mV , 50 mV

Minimum Voltage Range Accuracy 0.091 mV

Number of Ranges 15

Simultaneous Sampling No

On-Board Memory 512 samples

Analog Output

Channels 2

Resolution 12 bits

Max Voltage 10 V

Maximum Voltage Range -10 V , 10 VMaximum Voltage Range Accuracy 8.127 mV

Minimum Voltage Range 0 V , 10 V

Minimum Voltage Range Accuracy 5.685 mV

Update Rate 1 MS/s

Current Drive Single 5 mA

Digital I/O

Bidirectional Channels 8

Input-Only Channels 0

Output-Only Channels 0

Number of Channels 0 , 8

Timing Software

Logic Levels TTL

Input Current Flow Sinking , Sourcing

Output Current Flow Sinking , Sourcing

Programmable Input Filters No

Supports Programmable Power-Up States? No

Current Drive Single 24 mA

Current Drive All 192 mA

Watchdog Timer No

Supports Handshaking I/O? No

Supports Pattern I/O? No

Maximum Input Range 0 V , 5 V


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Maximum Output Range 0 V , 5 V

Counter/Timers

Counters 2

Number of DMA Channels 1

Buffered Operations Yes

Debouncing/Glitch Removal No

GPS Synchronization No

Maximum Range 0 V , 5 V

Max Source Frequency 20 MHz

Pulse Generation Yes

Resolution 24 bits

Timebase Stability 100 ppm

Logic Levels TTL

Physical Specifications

Length 17.5 cm

Width 10.7 cm

I/O Connector 68-pin male 0.050 D-type

Timing/Triggering/Synchronization

Triggering Digital , Analog

Synchronization Bus (RTSI) Yes


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APPENDIX H

I/O Connector Signal Description of NI DAQ 6070E


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instrumentation project 2011..temperature measuring system

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