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User
Manual

Thermocouple/
Millivolt Input
Module

(Cat. No. 1794-IT8)

Allen-Bradley

Summary of Contents for 1794-IT8

Page 1: ...User Manual Thermocouple Millivolt Input Module Cat No 1794 IT8 Allen Bradley ...

Page 2: ...ts such as those described in this publication Reproduction of the contents of this copyrighted publication in whole or in part without written permission of Allen Bradley Company Inc is prohibited Throughout this manual we make notes to alert you to possible injury to people or damage to equipment under specific circumstances ATTENTION Identifies information about practices or circumstances that ...

Page 3: ...ouple selection has been added for use in some European markets Calibration procedures have been revised to eliminate 1 method in order to better control calibration results Change Bars The areas in this manual which are different from previous editions are marked with change bars as shown to the right of this paragraph to indicate the addition of new or revised information New Information Updated...

Page 4: ...soc ii Summary of Changes Publication 1794 6 5 7 April 1997 ...

Page 5: ...e Units 1794 TB2 and TB3 shown 2 3 Installing the Module 2 4 Connecting Wiring for the Thermocouple mV Module 2 5 Example of Millivolt Input Wiring to a 1794 TB3 Terminal Base Unit 2 7 Example 3 wire Thermocouple Wiring to a 1794 TB3T Temperature Terminal Base Unit 2 7 Module Indicators 2 8 Chapter Summary 2 8 Chapter 3 Chapter Objectives 3 1 Block Transfer Programming 3 1 Sample programs for FLEX...

Page 6: ...ata into the Image Table 5 3 Thermocouple mV Input Module 1794 IT8 Image Table Mapping 5 3 Thermocouple mV Input Module 1794 IT8 Read 5 3 Thermocouple mV Input Module 1794 IT8 Write 5 4 Word Bit Descriptions for the 1794 IT8 Thermocouple mV Input Module 5 4 Defaults 5 7 Chapter 6 Chapter Objective 6 1 General Information 6 1 Tools and Equipment 6 2 Removing Lead Wire or Thermocouple Extension Wire...

Page 7: ...rst Case Accuracy for the Thermocouple mV Module A 7 Error Due to Open Circuit Current Through Loop Resistance A 8 Worst Case Repeatability for the Thermocouple mV Input Module A 8 Appendix B General B 1 B Platinum 30 Rhodium vs Platinum 6 Rhodium Type Thermocouples B 1 E Nickel Chromium vs Copper Nickel Constantan Type Thermocouple B 2 J Iron vs Copper Nickel Constantan Type Thermocouple B 2 K Ni...

Page 8: ...Table of Contents iv Publication 1794 6 5 7 ...

Page 9: ...odule Describes features capabilities and hardware components 2 How to Install Your Thermocouple mV Input Module Installation and connecting wiring 3 Module Programming Block transfer programming and programming examples 4 Writing Configuration to and Reading Status from Your Module with a Remote I O Adapter Describes block transfer write and block transfer read configurations including complete b...

Page 10: ...wing documents Catalog Descr pt on Publications Catalog Number Description Installation Instructions User Manual 1787 MGR DeviceNetManager Software User Manual 1787 6 5 3 Industrial Automation Wiring and Grounding Guidelines 1770 4 1 1794 1794 FLEX I O Product Data 1794 2 1 1794 ADN DeviceNet Adapter 1794 5 14 1794 6 5 5 1794 ASB C Remote I O Adapter 1794 5 46 1794 6 5 9 This preface gave you info...

Page 11: ...ny as eight I O modules terminal base contains a terminal strip to terminate wiring for thermocouple or millivolt inputs I O module contains the bus interface and circuitry needed to perform specific functions related to your application FLEX I O thermocouple mV modules are block transfer modules that interface analog signals with any Allen Bradley programmable controllers that have block transfer...

Page 12: ...ration data to the module using a BTW Flexbus External devices transmit analog signals to the module 2 The module converts analog signals into binary format and stores these values until the adapter requests their transfer 3 Your ladder program instructs the adapter to perform a BTR of the values and stores them in a data table 4 The adapter and module determine that the transfer was made without ...

Page 13: ...INPUT 2 INPUT 4 INPUT 6 INPUT 1 INPUT 3 INPUT 5 INPUT 7 THERMOCOUPLE INPUT 8 CHANNEL 3 1794 IT8 Allen Bradley OK The thermocouple mV module comes with 2 cold junction compensators These are designed to mount in designated positions on the temperature terminal base unit cat no 1794 TB3T Refer to chapter 2 for installation instructions for the cold junction compensator assemblies In this chapter you...

Page 14: ...Overview of FLEX I O and your Thermocouple mV Module 1 4 Publication 1794 6 5 7 ...

Page 15: ...ed to your module before installation If power is not applied the module position will appear to the adapter as an empty slot in your chassis If this product has the CE mark it is approved for installation within the European Union and EEA regions It has been designed and tested to meet the following directives EMC Directive This product is tested to meet Council Directive 89 336 EEC Electromagnet...

Page 16: ...ns Industrial Automation Wiring and Grounding Guidelines For Noise Immunity publication 1770 4 1 Guidelines for Handling Lithium Batteries publication AG 5 4 Automation Systems Catalog publication B111 The wiring of the terminal base unit is determined by the current draw through the terminal base Make certain that the current draw does not exceed 10A ATTENTION Total current draw through the termi...

Page 17: ...r ground from the thermocouple terminal base unit to any ac or dc discrete module terminal base unit Note Use this configuration if using any noisy dc discrete I O modules in your system Thermocouple module wiring separate from discrete wiring Thermocouple or Analog Module Note All modules powered by the same power supply must be analog modules for this configuration Note All modules must be analo...

Page 18: ...nsert it under backplane power When you remove or insert a module with field side power applied an electrical arc may occur An electrical arc can cause personal injury or property damage by sending an erroneous signal to your system s field devices causing unintended machine motion causing an explosion in a hazardous environment Repeated electrical arcing causes excessive wear to contacts on both ...

Page 19: ...TB3T These terminals on 1794 TB3 only V 24V dc 0 15 34 51 16 33 COM 24V dc common Connecting Wiring using a 1794 TB2 TB3 and TB3T Terminal Base Units 1 Connect the individual signal wiring to numbered terminals on the 0 15 row A on the terminal base unit Connect the high side to the even numbered terminals and the low side to the odd numbered terminals See Table 2 A 2 Connect shield return to the ...

Page 20: ...18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 34 1794 TB3 TB3T 0 15 34 51 16 33 A B C 1 51 34 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 0 15 34 51 16 33 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0 1794 TB2 A B C Table 2 A Wi...

Page 21: ...essary Example of Millivolt Input Wiring to a 1794 TB3 Terminal Base Unit 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 34 1794 TB3 0 15 34 51 16 33 Millivolt input Channel 1 Millivolt Source Channel 0 Terminals 0 1 and 17 Example of 3 wire Thermocouple Wiring to a...

Page 22: ...4 INPUT 6 INPUT 1 INPUT 3 INPUT 5 INPUT 7 THERMOCOUPLE INPUT 8 CHANNEL 3 1794 IT8 Allen Bradley OK Color State Meaning Red On Indicates a critical fault diagnostic failure etc Blinking Indicates a noncritical fault such as open sensor input out of range etc Green On Module is configured and fully operational Blinking Module is functional but not configured Off Module not powered In this chapter yo...

Page 23: ...rocessor s data table The processor user program initiates the request to transfer data from the module to the processor The transferred words contain module status channel status and input data from the module ATTENTION If the thermocouple mV module is not powered up before the remote I O adapter the adapter will not recognize the module Make certain that the thermocouple mV module is installed a...

Page 24: ...te instructions for your module A different block transfer control file is required for every module A sample program segment with block transfer instructions is shown in Figure 3 1 and described below Figure 3 1 PLC 3 Family Sample Program Structure EN BTR BLOCK XFER READ RACK GROUP MODULE CONTROL 7 0 0 B3 0 DATA FILE LENGTH B4 0 11 EN BTW BLOCK XFER WRITE RACK GROUP MODULE CONTROL 7 0 0 B3 0 DN ...

Page 25: ... 2 ER EN DN ER BTR BLOCK TRANSFER READ RACK GROUP MODULE DATA FILE LENGTH CONTINUOUS N BTW BLOCK TRANSFER WRITE RACK GROUP MODULE LENGTH CONTINUOUS N 2 1 0 N13 0 11 2 1 0 3 Program Action CONTROL N12 0 DATA FILE N13 20 CONTROL N12 5 N12 5 15 N12 0 15 Thereafter the program continuously per forms read block transfers Pushbutton The pushbutton allows the user to manually request a block transfer wri...

Page 26: ...es are not recommended for use with PLC 2 family programmable controllers due to the number of digits needed for high resolution In this chapter you learned how to program your programmable controller You were given sample programs for your PLC 3 and PLC 5 family processors Chapter Summary ...

Page 27: ...e transferred to the module using a block transfer write instruction The software configurable features available for the thermocouple module are input output range selection including full range and bipolar selectable first notch filter data reported in oF oC unipolar or bipolar count Note PLC 5 family programmable controllers that use 6200 software version 5 2 or later programming tools can take...

Page 28: ...300 to 10000 0 1oC Type J 195 to 1200oC 1950 to 12000 0 1oC Type K 230 to 1372oC 2300 to 13720 0 1oC Type R 50 to 1768oC 500 to 17680 0 1oC Type S 50 to 1768oC 500 to 17680 0 1oC Type T 195 to 400oC 1950 to 4000 0 1oC Type N 270 to 1300oC 2700 to 13000 0 1oC Type C 0 to 2315oC 0 to 23150 0 1oC Type L 175 to 800oC 1750 to 8000 0 1oC Type B 572 to 3272oF 5720 to 32720 0 1oF Type E 382 to 1832oF 3820...

Page 29: ...is a function of the number of inputs used and the first notch filter Both of these influence the time from a thermocouple input to arrival at the backplane Throughput in Normal Mode A D Filter First Notch Frequency effective resolution 10Hz 16 bits 25Hz 16 bits 50Hz 16 bits 60Hz 16 bits 100Hz 16 bits 250Hz 13 bits 500Hz 11 bits 1000Hz 9 bits Number of channels scanned System Throughput in ms and ...

Page 30: ...put Module 1794 IT8 Image Table Mapping Module Image I O Image Input Data Channel 0 Input Data Channel 1 Input Data Channel 2 Input Data Channel 3 Input Data Channel 4 Input Data Channel 5 Input Data Channel 6 Input Data Channel 7 Underrange Calibration Mask Thermocouple Type Input Size Output Size 0 to 3 Words 1 to 11 Words Reserved Overrange Calibration Status Thermocouple Type Configuration The...

Page 31: ...4 00 15 00 17 Channel 3 Input data Read Word 5 00 15 00 17 Channel 4 Input data Read Word 6 00 15 00 17 Channel 5 Input data Read Word 7 00 15 00 17 Channel 6 Input data Read Word 8 00 15 00 17 Channel 7 Input data Read Word 9 00 07 00 07 Underrange bits these bits are set if the input signal is below the input channel s minimum range 08 15 10 17 Overrange bits these bits are set if 1 the input si...

Page 32: ...ll Scale step input in 60 times the selected first notch filter time shown on page 4 3 Default filter disabled 03 05 03 05 A D Filter First Notch Frequency Bit 05 04 03 Definition 0 0 0 10Hz default 0 0 1 25Hz 0 1 0 50Hz 0 1 1 60Hz 1 0 0 100Hz 1 0 1 250Hz 1 1 0 500Hz 1 1 1 1000hZ 06 06 Calibration High Low bit This bit is set during gain calibration reset during offset calibration 07 07 Calibratio...

Page 33: ...o 2372oF 1 0 1 0 L 175 to 800oC 283 to 1472oF 1 0 1 1 Reserved 1 1 0 0 Module reports cold junction temperature for channels 00 03 1 1 0 1 Module reports cold junction temperature for channels 04 07 1 1 1 0 Reserved 1 1 1 1 No sensor connected do not scan 04 07 04 07 Channel 1 Thermocouple Type see bits 00 03 08 11 10 13 Channel 2 Thermocouple Type see bits 00 03 12 15 14 17 Channel 3 Thermocouple...

Page 34: ...4 8 Writing Configuration to and Reading Status from your Module with a Remote I O Adapter Publication 1794 6 5 7 April 1997 ...

Page 35: ...dule User Manual publication 1794 6 5 5 Output data is received by the adapter in the order of the installed I O modules The Output data for Slot 0 is received first followed by the Output data for Slot 1 and so on up to slot 7 The first word of input data sent by the adapter is the Adapter Status Word This is followed by the input data from each slot in the order of the installed I O modules The ...

Page 36: ... o ul ault 3 This bit is set 1 when an error is detected in slot position 3 I O Module Fault 4 This bit is set 1 when an error is detected in slot position 4 5 This bit is set 1 when an error is detected in slot position 5 6 This bit is set 1 when an error is detected in slot position 6 7 This bit is set 1 when an error is detected in slot position 7 Node Address Changed 8 This bit is set 1 when t...

Page 37: ...hput FLEX I O thermocouple module data table mapping is shown below Thermocouple mV Input Module 1794 IT8 Image Table Mapping Module Image I O Image Input Data Channel 0 Input Data Channel 1 Input Data Channel 2 Input Data Channel 3 Input Data Channel 4 Input Data Channel 5 Input Data Channel 6 Input Data Channel 7 Underrange Calibration Mask Thermocouple Type Input Size Output Size 0 to 3 Words 1...

Page 38: ...pe Where FDF fixed digital filter bit Word Bit Descriptions for the 1794 IT8 Thermocouple mV Input Module Word Decimal Bit Octal Bit Description Read Word 1 00 15 00 17 Reserved Read Word 2 00 15 00 17 Channel 0 Input data Read Word 3 00 15 00 17 Channel 1 Input data Read Word 4 00 15 00 17 Channel 2 Input data Read Word 5 00 15 00 17 Channel 3 Input data Read Word 6 00 15 00 17 Channel 4 Input da...

Page 39: ...ta Type Bit 01 00 Definition 0 0 oC default 0 1 oF 1 0 Bipolar counts scaled between 32768 and 32767 1 1 Unipolar counts scaled between 0 and 65535 Bit 02 02 Fixed Digital Filter When this bit is set 1 a software digital filter is enabled This filter settles to 100 of a Full Scale step input in 60 times the selected first notch filter time shown on page 4 3 Default filter disabled 03 05 03 05 A D ...

Page 40: ...o 2315oC 32 to 4199oF 1 0 0 1 N 270 to 1300oC 450 to 2372oF 1 0 1 0 L 175 to 800oC 283 to 1472oF 1 0 1 1 Reserved 1 1 0 0 Module reports cold junction temperature for channels 00 03 1 1 0 1 Module reports cold junction temperature for channels 04 07 1 1 1 0 Reserved 1 1 1 1 No sensor connected do not scan 04 07 04 07 Channel 1 Thermocouple Type see bits 00 03 08 11 10 13 Channel 2 Thermocouple Typ...

Page 41: ...alog module you have 11 input words and 4 output words You can change the I O data size for a module by reducing the number of words mapped into the adapter module as shown in real time sizes Real time sizes are the settings that provide optimal real time data to the adapter module Analog modules have 15 words assigned to them This is divided into input words output words You can reduce the I O da...

Page 42: ...5 8 How Communication Takes Place and I O Image Table Mapping with the DeviceNet Adapter Publication 1794 6 5 7 April 1997 ...

Page 43: ...t detection current See Error Due to Open Circuit Current Through Loop Resistance in Appendix A Calibration can be accomplished using any of the following methods manual calibration as described below 6200 I O CONFIGURATION software version 5 2 or later refer to your 6200 software publications for procedures for calibrating DeviceNetManager Software refer to your DeviceNetManager software document...

Page 44: ...23 24 25 26 27 28 29 30 31 32 33 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 34 1794 TB3 TB3T 0 15 34 51 16 33 A B C Ω b Measure total loop resistance of both lead extension wires and thermocouple 1 Thermocouple or Sensor c If using a sensor other than a thermocouple disconnect the lead wires at the sensor and ti...

Page 45: ...ou can initiate BTWs to the module and read inputs from the module Important In order to allow the internal module temperature to stabilize energize the module for at least 40 minutes before calibrating Module calibration consists of Applying a reference to the desired input s Sending a message to the module indicating which inputs to read and what calibration step is being performed offset The mo...

Page 46: ...l done 1 NO YES NO YES Apply reference signal for gain calibration to each channel to be calibrated Retain corresponding bits in the calibration mask and set cal Hi Lo 1 Set cal clk 1 Set cal clk 0 and cal hi lo 0 NO YES NO YES Clear corresponding bits in the calibration mask BTR Legend Cal done 0 Cal done 0 Cal done 1 BTW BTW BTR BTW BTW BTR BTW BTR BTW BTW BTR BTW block transfer write block tran...

Page 47: ...CJC Note 2 CJC not required if using thermocouple for resistance only Note Use 1794 TB2 and TB3 terminal base units for millivolt inputs only These terminals not on 1794 TB2 Wiring Connections for the Thermocouple Module Thermocouple 1794 TB2 TB3 Terminal Base Units 1794 TB3T Terminal Base Unit2 Thermocouple Channel High Signal Terminal Low Signal Terminal Shield Return High Signal Terminal Low Si...

Page 48: ...als together and attach to the positive lead from the precision voltage source Connect all low signal terminals together and attach to the negative lead 3 After the connections stabilize use a block transfer write to set the bit s in the calibration mask that correspond to the channel s you want to calibrate to 1 Bits 08 through 15 in write word 0 4 Send another block transfer write to set the cal...

Page 49: ... 06 in write word 0 to 1 Set bits 08 through 15 in write word 0 if calibrating all inputs at one time 4 Send another block transfer write to set the cal clk bit 07 in write word 0 to 1 5 Monitor the cal done bit 09 in read word 10 If the calibration is successful the cal done bit will be set to 1 Verify that the bad cal bit 10 in read word 10 and the cal range bit 08 in read word 10 are not set 0 ...

Page 50: ...ts for all inputs at once proceed as follows 1 Connect 0 000V across each input channel Connect all high signal terminals together and attach to the positive lead from the precision voltage source Connect all low signal terminals together and attach to the negative lead 2 Apply power to the module for 45 minutes before calibrating 3 Click on Configure for the slot containing the thermocouple modul...

Page 51: ...pril 1997 4 Click on to get to the calibration screen 5 Click on the channels you want to calibrate 6 Click on the radio button for offset calibration Then click on 7 When calibration is complete a notification will appear on the calibration status line ...

Page 52: ...each input channel Connect all high signal terminals together and attach to the positive lead from the precision voltage source Connect all low signal terminals together and attach to the negative lead 2 Click on the channels you want to calibrate 3 Click on the radio button for gain calibration Then click on 4 When calibration is complete a notification will appear on the calibration status line ...

Page 53: ...t there is an implied decimal point to the left of the last 2 digits For example channel 0 data value reads 7500 The actual reading is 75 00mV After both offset and gain calibrations are successful click on You will be returned to the module configuration screen Either save to the device adapter or save to a file by clicking on the appropriate button ...

Page 54: ...6 12 Calibrating Your Module Publication 1794 6 5 7 April 1997 If you attempt to close without saving your configuration information by clicking on the button you will be prompted to save the changes ...

Page 55: ...nt or offset binary unipolar Normal Mode Noise Rejection 60db 60Hz Common Mode Rejection 115db 60Hz 100db 50Hz Common Mode Input Range 10V Channel to Channel Isolation 10V System Throughput 325ms 1 channel scanned programmable to 28ms 2 6s 8 channels scanned programmable to 224ms Settling Time to 100 of final value Available at system throughput rate Open Circuit Detection Out of range reading ups...

Page 56: ...ironmental Conditions Operational Temperature Storage Temperature Relative Humidity Shock Operating Non operating Vibration 0 to 55oC 32 to 131oF See derating curve 40 to 85oC 40 to 185oF 5 to 95 noncondensing operating 5 to 80 noncondensing nonoperating 30 g peak acceleration 11 1 ms pulse width 50 g peak acceleration 11 1 ms pulse width Tested 5 g 10 500Hz per IEC 68 2 6 Agency Certification whe...

Page 57: ...olution Curves for Thermocouples Type B Thermocouple 10 100Hz 250Hz 500Hz 1000Hz Resolution C F 0 80 1 44 6 40 11 52 25 60 46 08 102 4 184 3 0 70 1 26 5 60 10 08 22 40 40 32 89 60 161 3 0 60 1 08 4 80 8 64 19 20 34 56 76 80 138 2 0 50 0 90 4 00 7 20 16 00 28 80 64 00 115 2 0 40 0 72 3 20 5 76 12 80 23 04 51 20 92 16 0 30 0 54 2 40 4 32 9 60 17 28 38 40 69 12 0 300 508 150 238 0 32 150 302 300 572 ...

Page 58: ...6 40 5 76 12 80 23 04 0 300 508 150 238 0 32 150 302 300 572 450 842 600 1112 750 1382 900 1652 1050 1922 1200 2192 Temperature C F Type C Thermocouple 10 100Hz 250Hz 500Hz 1000Hz Resolution C F 0 25 0 45 2 00 3 60 8 00 14 4 32 00 57 60 0 15 0 27 1 20 2 16 4 80 8 64 19 20 34 56 0 300 508 0 32 300 572 1500 2732 900 1652 1200 2192 Temperature C F 0 20 0 36 1 60 2 88 6 40 11 52 25 60 46 08 0 10 0 18 ...

Page 59: ... 280 2 304 5 120 9 216 0 300 508 150 238 0 32 150 302 300 572 450 842 600 1112 750 1382 900 1652 1050 1922 1200 2192 Temperature C F 0 020 0 036 0 160 0 288 0 640 1 152 2 560 4 608 Type K Thermocouple 10 100Hz 250Hz 500Hz 1000Hz Resolution C F 1 000 1 800 8 000 14 40 32 00 57 60 128 0 230 4 0 800 1 440 6 400 11 52 25 60 46 08 102 4 184 3 0 600 1 080 4 800 8 640 19 20 34 56 76 80 138 2 0 400 0 720 ...

Page 60: ...C F 0 20 0 36 1 60 2 88 6 40 11 52 25 60 46 08 600 1112 1350 2462 1800 3272 1650 3002 Type S Thermocouple 10 100Hz 250Hz 500Hz 1000Hz Resolution C F 0 60 1 08 4 80 8 64 19 20 34 56 76 80 138 2 0 50 0 90 4 00 7 20 16 00 28 80 64 00 115 2 0 40 0 72 3 20 5 76 12 80 23 04 51 20 92 16 0 30 0 54 2 40 4 32 9 60 17 28 38 40 69 12 0 300 508 150 238 0 32 150 302 300 572 450 842 1500 2732 750 1382 900 1652 1...

Page 61: ...32 9 60 17 28 38 40 69 12 0 300 508 150 238 0 32 150 302 300 572 450 842 Temperature C F 0 20 0 36 1 60 2 88 6 40 11 52 25 60 46 08 0 10 0 18 0 80 1 44 3 20 5 76 12 80 23 04 600 1112 Type N Thermocouple 10 100Hz 250Hz 500Hz 1000Hz Resolution C F 1 00 1 80 8 00 14 40 32 00 57 60 128 0 230 4 0 60 1 08 4 80 8 64 19 20 34 56 76 80 138 2 0 40 0 72 3 20 5 76 12 80 23 04 51 20 92 16 0 300 508 150 238 0 3...

Page 62: ...rature C F 300 572 800 1472 100 148 Worst Case Accuracy for the Thermocouple mV Module Input Type Accuracy 25oC Accuracy 77oF Temperature Drift 0 60oC 32 oF B 3 70oC 6 66oF 0 710oC oC 0 710oF oF E 0 51oC 0 92oF 0 104oC oC 0 104oF oF J 0 68oC 1 22oF 0 130oC oC 0 130oF oF K 1 00oC 1 80oF 0 186oC oC 0 186oF oF R 3 16oC 5 69oF 0 601oC oC 0 601oF oF S 3 70oC 6 67oF 0 651oC oC 0 651oF oF T 0 67oC 1 21oF...

Page 63: ...ror Worst Case Repeatability for the Thermocouple mV Input Module Input Type Repeatability with Filter oC oF Repeatability without Filter oC oF B 1 00oC 1 80oF 2 00oC oC 3 60oF oF E 0 16oC 0 29oF 0 32oC oC 0 58oF oF J 0 20oC 0 36oF 0 40oC oC 0 72oF oF K 0 28oC 0 50oF 0 56oC oC 1 00oF oF R 1 10oC 1 98oF 2 20oC oC 3 96oF oF S 1 00oC 1 80oF 2 00oC oC 3 60oF oF T 0 27oC 0 54oF 0 54oC oC 1 08oF oF N 0 ...

Page 64: ...Specifications A 10 Publication 1794 6 5 7 March 1997 ...

Page 65: ...he reference junction temperature of the thermocouple does not need to be controlled or even known as long as it is between 0 and 50C Studies have shown that a 0 1 percent change in the Rhodium content of the Pt 30 Rh thermoelement produces a corresponding change in the thermocouple voltage of about 15uV i e 1 3C at 1500C In contrast a change of only 01 in the Rhodium content of Pt 6 Rh thermoelem...

Page 66: ...mposition changes under thermal neutron irradiation since the copper is converted to nickel and zinc ASTM Standard E230 72 in the Annual Book of ASTM Standards 1972 specifies that the standard limits of error for the Type E commercial thermocouples be 1 7C between 0 and 316C and 1 2 percent between 316 and 871C Limits of error are not specified for Type E thermocouples below 0C Type E thermocouple...

Page 67: ...ations especially the latter seriously affect the thermoelectric properties of iron and therefore the Type J thermocouples If Type J thermocouples are taken to high temperatures especially above 900C they will lose accuracy of their calibration when they are recycled to lower temperatures ASTM Standard E230 72 in the Annual Book of ASTM Standards 1972 specifies that the standard limits of error fo...

Page 68: ...mocouples may be used at temperatures up to about 1350C for short periods with only small changes in calibration They should not be used in sulfurous reducing or alternately reducing and oxidizing atmospheres unless suitably protected with protecting tubes They should not be used in vacuum at high temperatures for extended times because the Chromium in the positive thermoelement vaporizes out of s...

Page 69: ...oelectric voltage unless it is annealed out The thermoelectric voltages of platinum based thermocouples are sensitive to their heat treatments In particular quenching from high temperatures should be avoided ASTM Standard E230 72 in the Annual Book of ASTM Standards 1972 specifies that the standard limits of error for Type S and R commercial thermocouples be 1 4C between 0 and 538C and 1 4 between...

Page 70: ...oelements may occur Type T thermoelements are not well suited for use in nuclear environments since both thermoelements are subject to significant changes in composition under thermal neutron irradiation The copper in the thermoelement is converted to nickel and zinc Because of the high thermal conductivity of Type TP thermoelements special care should be exercised in the use of the thermocouples ...

Page 71: ...old junction compensators 1 3 cold junction connection wiring 2 6 communication between module and adapter 1 2 compatible terminal bases 2 5 configurable features 4 1 connecting CJC 2 6 connecting wiring 2 5 6 6 considerations pre installation 2 1 curent draw through base units 2 2 curve derating A 2 supply voltage vs ambient temperature A 2 curves resolution A 3 D daisy chaining wiring 2 3 defaul...

Page 72: ... removing and replacing under power RIUP 2 4 repeatability worst case A 8 resolution curves A 3 type B thermocouple A 3 type C thermocouple A 4 type E thermocouple A 3 type J thermocouple A 4 type K thermocouple A 5 type N thermocouple A 7 type R thermocouple A 5 type S thermocouple A 6 type T thermocouple A 6 S sample program 3 4 scaling 4 2 software DeviceNetManager 5 1 specifications thermocoup...

Page 73: ...n manual accessibility info not in manual text illustration Technical Accuracy Completeness What information is missing Clarity Sequence What is not in the right order What is unclear Other Comments Use back for more comments Your Name Location Phone Return to Marketing Communications Allen Bradley Co 1 Allen Bradley Drive Mayfield Hts OH 44124 6118 Phone 216 646 3176 FAX 216 646 4320 Publication ...

Page 74: ...E NECESSARY IF MAILED IN THE UNITED STATES BUSINESS REPLY MAIL FIRST CLASS MAIL PERMIT NO 18235 CLEVELAND OH POSTAGE WILL BE PAID BY THE ADDRESSEE 1 ALLEN BRADLEY DR MAYFIELD HEIGHTS OH 44124 9705 PLEASE REMOVE PLEASE FASTEN HERE DO NOT STAPLE ...

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