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1. a contact person at your organization Please make sure that the RMA number is prominently displayed on the outside of the box e Thank You 46
2. Channel BridgeA BridgeB BridgeC BridgeD NullPot Arm CSC s CC po RX7 RX8 RX9 RXIO RXI2 RX53 O 2 RXI3 RXi4 RXI5 RXI6 RXI8 RX54 O 3 RXI9 RX2 RX21_ RX22 RXI4 RX55 o 4 R25 RX26 RX2 7 RX28 RX30 RX56 pS RXI RX32 RX33 RX34 RX36 RX57 pT RX37 RX38 RX39 RX40 RX42 RX58 Some values of precision resistors are available from CyberResearch 7 8 2 Nulling Potentiometers amp Arm Resistor Each circuit has a position for a nulling potentiometer and associated arm resistor The purpose of the nulling arm is to allow you to zero the reading of strain at a given strain position There is no formula to use to select the nulling potentiometer and arm resistor Bridge resistor values and total gain selected for the CYEXP GP will affect adjustability for a given nulling circuit An average value for the arm resistor is 10k ohms Start with that and adjust as required 7 8 3 Strain Gauge Bridge Configuration Examples Following are three typical strain gauge bridge configurations They are by no means the only way to connect a strain gauge to the CYEXP GP For example there is no rule that says the A leg must be the strain gauge on a 4 bridge implementation The examples below show how to translate strain to input voltage for the strain gauge configuration used to measure simple bending strain Other types of stress and strain axial torsion shearing etc are
3. SENSE High side of input SENSE Hardwired to other SENSE same function IEXC Excitation current The use of the terminals is dependent on the type of sensor you have connected to the input circuit and the nomenclature on the terminals has been chosen to make the most sense for bridge and RTD sensors For voltage and thermocouple sensors the names on the terminals are not typical Please refer to the section on the measurement you are making in order to learn how to use the terminals 9 3 8 Verifying the Installation For verification of the installation leave any switches or jumpers not mentioned above in their default positions Each of the gain switches CHO through CH7 and 17 7 should be off toward the upper edge of the board for a gain of X1 unity gain The channel configuration switches labeled IN CONFIG should be left in the default position the switches labeled 4 in the ON position and those labeled 3 in the OFF position the label is printed on the board not the switch To verify the installation use the InstaCal program installed on your computer This software came with your A D board if you bought the board from the same manufacturer as the CYEXP GP If your A D board is not from the same manufacturer but is compatible please call technical support and request a copy of InstaCal Use InstaCal s TEST option to verify that a signal present at one of the CYEXP GP inputs can be read You will not need t
4. These terminals are shown in Figure 4 4 to the right To connect a voltage signal to the input circuit you need only use three screw terminals These are SENSE Signal high or CH HI on a DAS board SENSE Signal low or CH LO on a DAS board Must be jumpered to P for single ended n T NE m4 KG Q 5 Q a gt amp Z 5 e BS nS m o EMS NOWWOD JO NI SLTOA NI SLTOA SLTOA NOLLVIIDXH d NI SLTOA LNANAND NOILVLIOX P Low Level Ground LLGND iud l T F vu lest q y u u 2 x 2 g amp CHO Figure 4 4 Input Screw Terminals 4 7 1 Single Ended Inputs A single ended input has two wires connected to the CYEXP GP a signal high and a Low Level Ground LLGND The LLGND signal must be the same ground the PC is on Single ended mode is selected by installing a jumper between the signal low SENSE and ground P The SENSE terminal is then connected to the signal ground and the SENSE terminal is connected to the signal 4 7 2 Floating Differential A floating differential input has two wires from the signal source and a 10K ground reference resistor installed at the CYEXP GP input The two signals from the signal source are Signal High and Signal Low The reference resistor is connected between the CYEXP GP SENSE and P pins and the Signal Low is connected to the SENSE terminal The SENSE terminal is connected to the Signal High A floating differential ho
5. This would also result in 5V to the DAS board The advantage to using a lower excitation voltage is that it causes less power dissipation on the strain gauge element itself reducing thermal expansion from self heating 7 9 Verifying the Installation To verify the installation use the InstaCal program installed on your computer This software came with your A D board if you bought the board from the same manufacturer as the CYEXP GP If your A D board is not from the same manufacturer but is compatible please call technical support and request a copy of InstaCal Use InstaCal s TEST option to verify that a signal present at one of the CYEXP GP inputs can be read 38 Power Consumption 5V Analog Input Section Input Amplifier Type Number of Channels Gains Gain Error Gain 1 2 5 Gain 10 25 Gain 100 250 Gain 1000 2500 Linearity Gain 1 2 5 Gain 10 25 Gain 100 250 Gain 1000 2500 Input Offset Gain TC Gain 1 Gain 100 Gain 1000 Input Offset TC Gain 1 2 5 Gain 10 25 Gain 100 250 Gain 1000 2500 Common Mode Range CMRR Gain 10 25 100 250 1000 2500 Gain 1 2 5 Absolute Maximum Input Channel to Channel Settling Time SV step to 01 MUX Switching Time SV step to 01 Miscellaneous 8 SPECIFICATIONS 380mA typical 533mA maximum INA102 8 differential Each channel individually switch selectable for X1 X10 X100 or custom and board gain switch selectable for X1
6. Vovur lexc Rem GAIN Normally the CYEXP GP supplies 1 mA of excitation current The choices for standard gains are 1 10 25 and 100 Higher gains are possible but are not generally practical for RTD applications Thus if you want to measure temperature in the range of 200 to 400 C with the RTD listed above the maximum voltage output would be V 0 001 247 04 0 24704 24 If gain is set to X10 the DAS board will see 2 474 volts This is ideal for a DAS board with a 2 5V unipolar range If the gain were set to X25 the output would be 6 185 volts The DAS board would have to be set in the 0 to 10 volt range If you are limiting your range of interest to 200 to 100 C a common range the calculations are V 0 001 138 50 0 1385 Gain of 10 1 385V Gain of 25 3 4625V In this case a gain of X25 and a DAS range of 0 to 10 volts would be best A 12 bit A D converter would be using 69 of its range of 4096 counts or a total of 2836 counts The converter would be able to resolve to 0 035 degrees C That is more than enough converter resolution even though you are not using the full range of the DAS board in this example If your DAS board has 16 bits of resolution the DAS board would resolve to 0 0022 degrees This is far in excess of the accuracy of the RTD The stages of gain you choose are not only dependent on the RTD you choose but on the range of temperature you are measuring Use the equation above to fine tu
7. 2 Connecting to a DAS16 Series A D Board Connection to a DAS16 series board requires a special 37 conductor cable CBL MX10 since pin relationship of CYEXP and DAS16 signals is not 1 1 Install the CBL MX10 cable connector labeled MUX into the P1 connector of the CYEXP GP board and the other end into the DAS16 series board s analog connector 3 4 3 Other A D Boards For other boards use the connector diagram in in Figure 3 4 to construct a cable or call us and f N discuss the possibility of a custom pasisiicnd w e manufactured cable OUTPUT 8 LLGND 18 r 2 a OUTPUT 9 17 The signals from the CYEXP GP are OUTPUT 10 35 OUTPUT 2 voltages from each channel and an analog oupurn os e 2E OUIRULS ground There should be no voltage between oururn u ol mmm the analog ground and the power ground ors g ol Omm i SODU p e 31 OUTPUT 6 The MUX address lines control the setting of ours u WO e 30 OUTPUT7 the channel multiplexer When all are low the SHUNTCALIBRATION 19 Bi oe ousnOMeC mux is set to channel 0 The lines are binary MUX ADDR 3 gt 0 e 28 POWER GROUND coded MUXADDRI1 is the LSB and MUXADDR2 s e MUXADDR3 is the MSB MUXADDRI 7 ee f NC 6 gt Ne A jumper CH SEL selects which output te 4 NC channel is read by the DASO8 or DAS16 wo 4 BO e 3 NC board a 0 2 NC K j e e 21 NC NG i e 20 NC L A Figure 3 4 37 Pin Connectors 3 5 Powering The CY
8. 2500 would then present a maximum voltage of 2 5V to the DAS board 37 Full Bridge Example Full bridge strain gauges consist of all four bridge resistors Figure 7 8 Obviously no bridge completion resistors are installed on the board when using this configuration EXCITATION VOLAGE EXCITATION VOLTS SENSE LOW Null Pot EXCITATION VOLTS SENSE HIGH TO CHANNEL 80Hz Low MULTIPLEXOR Pass Filter Figure 7 8 Full Bridge Simplified Schematic Full Cridge Calculations With four active strain gauge elements these are four times more sensitive than a 1 4 bridge All four resistors are strain gauges and are attached to the beam in the following configuration Gauge resistors C and B are on the bottom Their resistance decreases under the resultant compression but bridge voltage increases Gauge resistors D and A are on the top of the beam Their resistance increases under the resultant tension and bridge voltage likewise increases equal in magnitude to the changes in D and A Vor 10V 350 0 175 350 0 175 350 0 175 350 0 175 350 0 175 350 0 175 Vor 10V 350 0 175 700 349 825 700 Vir 5 00mV Choosing a gain of X1000 presents 5V to the DAS board covering its entire 5V unipolar range An excitation voltage of 4V could be been used in combination with a gain of 2500 X1000 on the input channel and X2 5 on the output
9. GP located near the 37 pin connector selects the A D board family as DASO8 or DAS16 E a E Figure 3 1 shows the jumper set to use the CYEXP GP with a CYDAS 8 family board DASO8 DAS16 Figure 3 1 DAS Family Select 3 2 Setting The Output Channel Jumpers labeled CH SEL located near the 37 pin connector select the A D board channel that the output from the active sensor will be connected to 37 Pin OUTPUT CHANNEL CONNECTORS SELECT JUMPER Ea 37 0o bhod v p26 sia oe INPUT 0 Ww v lt 3 4 Ooo pa INPUT 1 I Od 7 x 1 32 OF B56 i INPUT 2 PORD a 31 m i aan ce z INPUT 3 C lt Y Q i ne or4 a INPUT 4 l 18 H 8 D l Zz i1 D9 Z INPUT 5 beste lt 1 16 a ve LORDS 2 INPUT 6 eid y INPUT 7 14 Tea Je 13 ped ARG EPE A 11 zm I I I I Io MUX ADDR 3 I 1MUX ADDR 2 1 8 _IMUX ADDR 1 7 Q I oe I I kasepna I P1 amp P2 Figure 3 2 Output Channel Select Jumper There are three groups of 16 position jumpers One jumper group determines the signal output channel one jumper group determines the excitation voltage output channel and one determines the Cold Junction Compensation CJC output channel Signal output is always used CJC output is used only with thermocouples and excitation output may be used with bridge sensors There are 16 jumper locations for each function Each corresp
10. If you are not using the Universal Library check your software documentation before selecting a channel Failure to supply the CJC reference by installing the jumper on the correct channel will result in inaccurate temperature calculations by the software 17 The jumper for the CJC channel select Figure 5 1 01234567 8 9101112131415 looks just like the jumper for output channel eccclejeoce coececocece eooo eee selection eoceceecone Set this jumper according to the instructions for the CHANNEL 4 SELECTED FOR COLD JUNCTION SENSOR OUTPUT software package you are using CJC SEL Figure 5 1 CJC Channel Select Jumper Pad The CJC uses one analog input channel of the A D board The channel selected must be unique the CJC SEL jumper must not be set to the same number as that for CH SEL jumper or VEXC SEL jumper on this board or any other EXP board that may be daisy chained to this board 5 3 Input Configuration For thermocouple measurement the channel input configuration switches must be set for two wire measurement Also a ground reference should be established and open thermocouple detection should be enabled These options are selected by setting some switches and closing some solder pads on the underside of the CYEXP GP 5 3 1 Setting the Input Configuration A channel configuration switch is associated with each channel The switch is used to configure the input circuit for two or four wire measurements When m
11. common mode range NOTE If you want to change the use of the input circuit to an RTD or bridge sensor remove the solder that closes the G pad and the TC pad also 5 4 Determining the Appropriate Gain The voltage from a thermocouple must be amplified in order to take advantage of the A D board s full resolution Without amplification you would not get much resolution from thermocouples as you can see in the tables below Typical gain settings for use with thermocouples are between X10 and X250 Tables 5 3 and 5 4 below may be used to help determine the appropriate gain to use for the temperature range and thermocouple type in use Table 5 3 Resolution vs Thermocouple Gain Settings for a 5V 12 bit A D Type Output Min C Max C C bit C bit C bit C bit uV C X10 X100 X250 X1000 J 51 0 750 4 78 0 48 0 19 0 04 K 40 200 1 250 6 1 0 61 0 24 0 06 T 40 200 350 6 1 0 61 0 24 0 06 E 62 200 900 3 0 39 0 16 0 03 S 7 0 1 450 34 9 3 49 14 0 35 R 7 0 1 450 34 9 3 49 14 0 35 A J type thermocouple outputs 51mV per degree centigrade at 20 C At a gain of 100 a 12 bit A D on the 5V range resolves to 0 00002442 volts per bit 24 42uV bit With an output of 51mV C that represents about 0 5 C bit Look under the gain of 100 for a J type and you will find 0 48 C bit The table below shows the thermocouple output voltage at maximum temperature amplified by four p
12. eee 7 3 4 2 Connecting to a DAS16 Series A D Board 0 00 ene 7 3 4 3 Other A D Boards Gage eani eae ye Meera ed Noe a Mediate Bawa aes ken ee 7 3 5 Powering The CYEXP GP cei icine dah actin ioe ie 84 ONG YR RR ARE 8 J Power Source SWCD ceasitoa chads tad we sthega heaton baa een e aeaa 8 3 5 2 Powering with the 37 Pin Connector 0 0 cece cette eens 8 3 5 3 Powering with the Molex Connector 0 000 c ccc cence 8 3 5 4 Powering Through the Power Screw Terminals 0000 c eee eae 8 3 6 Daisy Chaining CYEXP GP Boards 0 0000 9 3 7 Connecting a Test Voltage 00 cette eens 9 3 8 Verifying the Installation 0 0006 eees 10 4 CONFIGURATION FOR VOLTAGE MEASUREMENT 11 4 1 Channel Selection isc ecteiee amp cruesa x caddie iea dlek sn ee Gutlen wea CANE a ee wD 11 4 2 Powering the CV EXP GP 5 eS ER BENS SES BEDE PEER PG 11 4 3 Determining The Appropriate Gain 0 000 11 4 4 Setting the Gain a hae deh bon es Ree wale a A Cool a e Gal ARN cies Se kt 12 BAN SEUINE OAT Galli siari Ta ee lial ah E Me AY Shere Ay hae RERA de A 12 4 4 2 Setting Channel Gain c0 5 4 h0y ev Re eee ed oR eR eee Rae Ree 13 4 5 Attenuation 55 Foe eRe VARS Spek MACs be ea Kite A ReN Oe Rae ges 13 4 6 Setting the Input Configuration 0 00 00 14 4 7 Connecting Voltage Signals 0 ccc nee eee 14 4 7 1 Single Ended
13. gauges have Gauge Factors of 2 to 2 1 This means that the resistance will change twice as much as the strain does A change of 1 micro strain means that the resistance of the strain gauge has changed by 2 ppm or 0002 0001 x 2 For a 350 ohm strain gauge with GF 2 a lue change results in a resistance change of Resistance change SG Resistance x change in length x Gauge Factor 350 ohm x 000001 x 2 0 0007 ohm 9 1 2 Specification of Strain Gauges Metal Foil gauges are available in 120 350 and 1000 ohms Semiconductor strain gauges exist and have resistance of up to 10000 ohms They can readily be used with the CYEXP GP but may not be as linear as metal foil gauges Maximum strain allowed is 3 to 5 depending on type and thickness of strain gauge material This means a limit of 30 000 to 50 000u or a maximum resistance change of 6 to 10 Strain Gauges are typically used to calculate a change in strain that is the difference between the unstrained and the strained state 9 2 Reference Material for Application of Strain Gauges The Bonded Electrical Resistance Strain Gage First Edition by William M Murray and William R Miller 1992 424 pages ISBN 0 19 507209 X Available from Society for Experimental Mechanics order OX 2 Strain Gage Users Handbook First Edition 1992 424 pages ISBN 0 912053 36 4 41 Published by Society for Experimental Mechanics order ELS 017 The Art of Practic
14. one for each side of the temperature sensitive resistor and one for the excitation current The current return and sense signals of one side are shared In the case of the CYEXP GP the shared 3 WIRE signals are unconventional The CYEXP GP is RTD a true clone of the original CYEXP GP and shares the unconventional circuit configuration m57 Note EXP GP uses non standard i l which is corrected on the CYEXP RTD i I i i I 3 wire RTD hookup EXCITATION CURRENT SENSE HIGH The unconventional configuration does not affect the quality of the measurement but if you are familiar with RTDs and use a standard connection please be mindful of this difference SENSE LOW EXCITATION CURRENT Figure 6 4 Three Wire RTD Hookup 6 8 3 Four Wire RTD Hookup A four wire RTD has four leads One to each side of the temperature sensitive resistor and an excitation current source and its return 27 These connections eliminate the fixed inaccuracy associated with the 2 wire RTD Since virtually no current flows on the sense lines there is no voltage drop in the sense lines Thus the error associated with BON CEE 2 wire RTDs is eliminated We recommend the 4 wire SENSE HIGH RTD but you must judge if the added cost is worth the ees additional accuracy SENSE LOW EXCITATION CURRENT Figure 6 5 Four Wire RTD Hookup 6 9 Verifying the Installation To verify the installation use
15. or X2 5 0 01 FS typical 0 15 FS maximum 0 02 FS typical 0 35 FS maximum 0 05 FS typical 0 40 FS maximum 0 20 FS typical 0 90 FS maximum 0 045 FS typical 0 045FS typical 0 075 FS typical 0 15 FS typical Each channel adjustable to zero 10ppm C typical 15ppm C typical 20ppm C typical 20uV C typical 6uV C typical 5 1uV C typical 5 1uV C typical 10V 100dB typical 94dB typical 50V 50 us 5 us typical Each input channel has a 79Hz low pass filter X2 5 gain is adjustable for zero error Jumper selects compatibility with DASO8 or DAS16 series Locations provided for bridge completion resistors for each channel Locations provided for bridge nulling pots and resistors for each channel 39 Analog Output Section Output Amplifier Type Number of Channels Maximum Output Range Current Drive Output Short Circuit Duration Output Coupling Output Impedance Miscellaneous Digital Input Output Section Digital Type DIn 0 through 2 DIn 3 Configuration Input Low Voltage DIn 0 through 2 DIn 3 Input High Voltage DIn 0 through 2 DIn 3 Voltage Excitation Section Excitation Voltages Sources for Excitation Voltage Current 5V Source from P1 4V VEXC 5V Source from P19 4V VEXC 12V Source 10V VEXC 15V External Source 10 VEXC Miscellaneous Current Excitation Section Excitation Channels Voltage Compliance Accuracy CJC Section Conversion Ratio Environmental Operating Temperature Rang
16. the InstaCal program installed on your computer This software came with your A D board if you bought the board from the same manufacturer as the CYEXP GP If your A D board is not from the same manufacturer but is compatible please call technical support and request a copy of InstaCal Use InstaCal s TEST option to verify that a signal present at one of the CYEXP GP inputs can be read 28 7 CONFIGURATION FOR RESISTANCE MEASUREMENTS Resistance measurements are made using the CYEXP GP by constructing a resistor bridge containing known resistor values that are to be compared to the resistor value to be measured This is known as a Wheatstone Bridge The typical application is a strain gauge Strain gauge sensors are variable resistance devices When installed in one leg of the resistor bridge as the unknown resistor their value can be measured The Wheatstone Bridge circuit is extremely sensitive to changes in resistance in one leg relative to the others There are various types of bridge sensors but the descriptions and examples here are for strain gauges 7 1 Channel Select The General Configuration section describes the channel selection setting the jumper and verifying the installation and operation of the CYEXP GP with your data acquisition board Configure your boards as described in that section before continuing with this section 7 2 VEXC Jumper Select There is a set of jumpers near the 37 pin connector labeled
17. the original selling price of the equipment The equipment warranty shall constitute the sole and exclusive remedy of any Buyer of Seller equipment and the sole and exclusive liability of the Seller its successors or assigns in connection with equipment purchased and in lieu of all other war ranties expressed implied or statutory including but not limited to any implied warranty of merchant ability or fitness and all other obligations or liabilities of seller its successors or assigns The equipment must be returned postage prepaid Package it securely and insure it You will be charged for parts and labor if the warranty period has expired Returns and RMAs If a CyberResearch product has been diagnosed as being non functional is visibly damaged or must be returned for any other reason please call for an assigned RMA number The RMA number is a key piece of information that lets us track and process returned merchandise with the fastest possible turnaround time PLEASE CALL FOR AN RMA NUMBER Packages returned without an RMA number will be refused In most cases a returned package will be refused at the receiving dock if its contents are not known The RMA number allows us to reference the history of returned products and determine if they are meeting your application s require ments When you call customer service for your RMA number you will be asked to provide information about the product you are returning your address and
18. the written approval of the President of CyberResearch Inc Life support devices and systems are devices or systems which are intended for surgical implantation into the body or to support or sustain life and whose failure to perform can be reasonably expected to result in injury Other medical equipment includes devices used for monitoring data acquisition modification or notification purposes in relation to life support life sustaining or vital statistic recording CyberResearch products are not designed with the components required are not subject to the testing required and are not submitted to the certification required to ensure a level of reliability appropriate for the treatment and diagnosis of humans Table of Contents LINTRODUCTION ceense ac it boda d he Pick be Raoe Lot aon debe ph HbA Phebe 1 2 SOFTWARE INSTALLATION 2 nee teens 3 3 GENERAL CONFIGURATION ooa e teens 5 3 1 A D Board Type Select Jumper 0 0 ee 5 3 2 Setting The Output Channel 0 00 eees 5 3 3 Configuring the A D Board 00 0 ccc eee eee 6 SSD ASUG Family SUID za sedrer ec aie eater Six neea eae mate peda ee ay 6 3 3 2 DAS16 Family Setup ye sec eos SPE BONS SS BEES HOE OP EE eS 6 333 All AND Boards 25 saey 1okhd dh caine bLae AG SAS ee aGee ew AGES Iae thee sehen 6 3 4 CONNECTING THE CYEXP GP TO THE A D BOARD 7 3 4 1 Connecting to a DASO08 Series A D Board 0 000
19. you to boost your signal to take full advantage of the resolution of the A D converter However when amplifying a signal any noise is amplified as well Amplification for ALL channels board output gain is switch selectable S17 for X1 or X2 5 Input amplification for EACH CHANNEL is switch selectable GAIN switches CHO through CH7 for X1 X10 X100 or X1000 A user specified gain may be set by supplying a precision resistor at position RX and setting the U option on the CH GAIN switch to ON 4 4 1 Setting Board Gain There is a switch on DIP switch block S17 labeled X1 and X2 5 Sliding this switch down amplifies the output of the multiplexers by 2 5 The factory default position up has a gain of 1 unity Refer to Figure 4 1 The X2 5 gain switch is useful in some voltage and bridge measurements If you desire a voltage gain of 2 5 25 250 or 2500 set this switch down Figure 4 1 Board Output Gain Switch Location For voltage measurements a gain of 2500 is very high and will reduce your signal to noise ratio The effect of this switch is multiplicative with respect to the individual channel gains For example if you have set an input channel gain to X100 and the board output gain to X2 5 the signal is amplified by 250 before it reaches the A D board 12 4 4 2 Setting Channel Gain Select a gain higher than unity by moving the switch for that gain down All other switches should be left in the UP posit
20. 0 Gain 1 PN 40 7 7 Setting the Input Configuration Channel Configuration Switch Voltages A channel configuration switch is associated with each channel Figure 7 5 The switches are used to configure the input circuits for voltage inputs thermocouple inputs 2 3 or 4 wire RTDs and bridges AeA U A U IN CONFIG AeA U A Q For bridge measurements on a particular channel set the switches labeled 4 to the ON down position for that channel Set the switches labeled 3 in the OFF up position CHO CHANNEL CONFIGURATION SWITCHES SET VOLTAGE THERMOCOUPLES OR 2 4 WIRE RTDs BOTH 4s ARE ON DOWN BOTH 3s ARE OFF UP Figure 7 5 Input Channel Configuration Switches 7 8 Configuring the Bridge As mentioned earlier in this chapter resistance measurements are made by constructing a bridge containing precision resistors with known values against which the unknown resistor is to be compared In strain gauge applications the strain gauge sensor itself may make up a quarter of this bridge half of 33 this bridge or the entire bridge Examples of each of these configurations follow Figure 7 6 is a schematic of the bridge circuit EXCITATION VOLAGE EXCITATION VOLTS SENSE LOW Null Pot SENSE LOW EXCITATION CURRENT EXCITATION VOLTS SENSE HIGH SENSE HIGH TO CHANNEL MULTIPLEXOR Pass Filter CURRENT SOURCE EXCITATION CURRENT VOLTAGE R
21. CYEXP GP 8 Channel General Purpose Multiplexing Panel USER S MANUAL VER 2 JAN 2001 No part of this manual may be reproduced without permission CyberResearch Inc www cyberresearch com 25 Business Park Dr Branford CT 06405 USA 203 483 8815 9am to 50m EST FAX 203 483 9024 Copyright 2001 All Rights Reserved January 2001 The information in this document is subject to change without prior notice in order to improve reliability design and function and does not represent a commitment on the part of CyberResearch Inc In no event will CyberResearch Inc be liable for direct indirect special incidental or consequential damages arising out of the use of or inability to use the product or documentation even if advised of the possibility of such damages This document contains proprietary information protected by copyright All rights are reserved No part of this manual may be reproduced by any mechanical electronic or other means in any form without prior written permission of CyberResearch Inc TRADEMARKS CyberResearch and CYEXP GP are trademarks of CyberResearch Inc Other product names mentioned herein are used for identification purposes only and may be trademarks and or registered trademarks of their respective companies e NOTICE e CyberResearch Inc does not authorize any CyberResearch product for use in life support systems medical equipment and or medical devices without
22. EFERENCE Figure 7 6 Bridge Circuit Resistance Change vs Sense Voltage Change This table shows how the measurement at the Leg Ohms_ Ohms A D board varies with respect to an increase Volts Volts or decrease of the resistance in one of the legs of the bridge Volts Volts Volts Volts Volts Volts Read the table by selecting the leg you are interested in and looking across that row to the volts indication under the column heading for the expected change in resistance For example if you are interested in leg A and want to know what the relative change in volts at the A D board will be if the resistance is increased look under Ohms The measured voltage will increase 7 8 1 Bridge Completion Resistors You likely will have to install bridge completion resistors on the CYEXP GP board to match the resistance of the external gauge Refer to Table 7 2 for their identities and locations If you are using a 1 4 bridge then you will have to install three precision resistors to complete the bridge If you are using a 2 bridge then you will need to install two resistors to complete the bridge If you are using a full bridge there are no resistors to install 34 Referring back to Figure 7 6 the legs of the bridge are labeled A B C and D Table 7 3 below matches the legs of the bridge to the resistor number nomenclature that appears on the CYEXP GP Table T 3 Bridge Co enui P or Identities
23. EL MULTIPLEXOR 80Hz Low Pass Filter Figure 7 6 4 Bridge Circuit Simplified Quarter Bridge Calculations The strain gauge is applied to the top of the beam This strain gauge takes the place of resistor A see Figure 7 6 Three other 350 ohm resistors B C and D complete the bridge circuit These are installed by the user in locations provided on the board or attached to the screw terminals As downward force is applied the strain gauge on the top of the beam will be stretched therefore its resistance will increase by Strain Gauge increase 350 ohm x 250 x 10 x 2 0 175 ohm Thus the value of gauge A under tension will be 350 175 ohms when the strain on the beam is 250ue Initially choosing an excitation voltage of 10V the bridge voltage is Vor 10V 350 700 350 350 350 OV After a downward force is applied Vor 10V 350 700 350 350 350 175 Vo 1 25mV Choosing an amplifier gain of X1000 results in 1 25V maximum presented to the DAS board Choosing an additional X2 5 overall output gain results in a total gain of 2500 thus sending 3 125V maximum to the DAS board This makes an optimum use of the 5V range 36 A Half Bridge Example For a bridge circuit Figure 7 7 the strain gauge has two resistive elements which are connected across two legs of the bridge The two legs would always be A amp C or B amp D The other two legs of the bridge must be populated wi
24. ET FOR 3 WIRE RTDs Figure 6 2 Channel Configuration Switches RTDs 26 6 8 Connecting RTDs To Screw Terminals The connections made to the screw terminal depend on the type of RTD you are using The inputs of the CYEXP GP are designed to provide the excitation and signal conditioning required for RTDs An RTD can have two three or four wires which you must connect to the CYEXP GP This section shows the three types of RTD connections and describes how to connect them to the input channels 6 8 1 Two Wire RTD Hookup A two wire RTD has two leads one to each side of the temperature sensitive resistor The excitation current is connected directly to the leads at the CYEXP GP screw terminals A two wire RTD is less accurate than the 4 wire ceeae acai type and so is not the first choice for the best CYEXP GP BOARD measurements The reason for the inaccuracy is 2 WIRE 1 that there is a slight resistance associated with the RTD ic EXCITATION CURRENT excitation current flowing in the sense leads and SENSE HIGH this resistance is added to the RTD s resistance The inaccuracy is determined by the wire gauge and length However as a general rule the difference in accuracy between the 2 and 4 wire es RTDs is often less than 0 1 of full scale Shorting Wires Between Terminals SENSE LOW I EXCITATION CURRENT I I Figure 6 3 Two wire RTD Hookup 6 8 2 Three Wire RTD Hookup A three wire RTD has three leads
25. EXP GP The CYEXP GP can be powered through the 37 pin cable the power screw terminal or the Molex connector The power that can be carried through the 37 pin connector is limited so we recommend using this source only when a single CYEXP GP is used The power required to run a CYEXP GP is dependent on the board configuration Remember that additional power will be drawn when the CYEXP GP is configured for resistance measurement bridge configuration due to the current required for each bridge 3 5 1 Power Source Switch One of the switches on the eight position DIP switch S17 near the output channel jumpers controls the source of the 5 volts power to the board Shown in Figure 3 5 it is the 3rd switch from the left When positioned down ON 5 COMP the 5V power is drawn from the personal computer through the signal cable PTT gt gt Wate When positioned up OFF REM 5V power is taken from the optional external 5V power connector the Molex connector labeled P19 or the 5V screw terminal connection fF N KF O O lt lt lt h z 2 Figure 3 5 Power Source Switch 3 5 2 Powering with the 37 Pin Connector You can power the CYEXP GP via the 37 pin cable No more than one CYEXP GP should be powered using the 37 pin cable This option is not available when using some A D boards If the A D board you are using supplies 5V at pin 29 or at pin 1 when using the CBL MX10 signal cable you can powe
26. Inputs 364 open 554 es eS a oe 15 4 7 2 Floa ng Differential sci 74 sand dh pe acaheny herenera an SP lee Aca eh pe acs oy SOLA 15 APD EUV ITIGEO IAL since iene hue oh Asi tice e e aes wh Aah andl later Adee tic Ail 15 4 8 Verifying the Installation 0 0 000000 eee 16 5 CONFIGURATION FOR THERMOCOUPLE MEASUREMENT 17 5 1 Selecting The Output Channel 0 17 5 2 Selecting The CJC Output Channel 0 cece eee eee 17 5 3 Input Configuration 206 ices peo ncn vendo gy w mecha wp esol gy Sea ease ees 18 5 3 1 Setting the Input Configuration 0 0 0 18 5 3 2 Enabling Open Thermocouple Detection OTD 00000005 18 5 3 3 Adding a Ground Reference 6 bs fee eyes SELON Ae elle OM eee EN oe hth 20 5 4 Determining the Appropriate Gain 00 000 20 5 5 Setn he Gain 37955 22 ee BID IEE NE Sh PEER IPE PUTER OE GRELEE POS 21 5 59 17 Setting Me BOAR Gain isee rosee sue td ees te ae aes Dek BE E RS eon 21 532 Settna the Channel Gal eteesi ein E a E ET AE R A oad 21 5 6 Verifying the Installation 0 00000 eees 22 6 CONFIGURATION FOR RTD MEASUREMENTS 00005 23 6 1 Channel Selection n nananana aaeeeo ee ee 23 6 2 VEXC Jumper Select rosino a ee eA A NAS Bee oe 23 6 3 CJC Jumper Selection gy 0 5 656 5 6 ee ik ARTA CRE ERT ERY CR ROS 23 6 4 Powering the CYEXP GP es 5 63 oes csie ents ous eke co
27. P blocks for each channel One is labeled GAIN and the other IN CONFIG The gain switches are labeled U user 10 100 and 1000 Set the gain of your choice by placing a slide switch into the ON down position The U switch and associated user resistor is of no value to RTD measurement since the minimum specified value produces a gain of X100 for which there is a switch A gain of X100 is the maximum you would use with an RTD 6 7 Input Configuration GAIN FOR CHANNELS 0 and 4 SET FOR A GAIN OF 10 SLIDER DOWN SELECTS GAIN ALL OTHERS TO BE OFF UP Figure 6 2 Channel Gain Switches RTDs may have 2 3 or 4 wires coming from the probe A switch labeled IN CONFIG must be set to match the number of wires on your RTD There is one switch per channel RTD Type IN CONFIG Setting 2 Wire 4 amp 40ON 3 amp 3 OFF 3 Wire 3 amp 3 ON 4 amp 4 OFF 4 Wire 4 amp 40ON 3 amp 3 OFF 6 7 1 Setting the Input Configuration A channel configuration switch is associated with each channel The switch is used to configure the input circuit for 2 3 or 4 wire RTDs Figure 6 2 Two and four wire RTDs share the same switch position Set both 4 switches ON down and both 3 switches OFF up For three wire RTDs set both 3 switches ON down and both 4 switches OFF up IN CONFIG KR WwW wW SET FOR 2 AND 4 WIRE RTDs IN CONFIG KR w KR i CHO Poe S
28. PC GROUND PC GROUND Figure 4 3 Voltage Divider For example if your signal is O to 10V it must be attenuated to 5V max for an attenuation of 2 1 or simply 2 Using 10k resistors 2 10K 10K 10K For any attenuation pick a suitable resistor for Rb Then use this formula to calculate Ra Ra A 1 x Rb You will need to construct the voltage divider remote from the CYEXP GP board 4 6 Setting the Input Configuration Channel Configuration Switch Voltages A channel configuration switch is associated with each channel Figure 4 5 The switches are used to configure the input circuits for voltage inputs thermocouple inputs 2 3 or 4 wire RTDs and bridges For voltage measurements on a particular channel set the IN CONEIG switches labeled 4 to the ON down position for that channel Set the switches labeled 3 in the OFF up position CHO CHANNEL CONFIGURATION SWITCHES SET VOLTAGE THERMOCOUPLES OR 2 4 WIRE RTDs BOTH 4s ARE ON DOWN BOTH 3s ARE OFF UP Figure 4 5 Channel Configuration Switches 4 7 Connecting Voltage Signals Voltage signals can be single ended or differential and the full scale may have to be matched to the range of the CYEXP GP and DAS board combination via amplification or attenuation To connect a voltage and make an accurate measurement each of these issues must be addressed see section 4 3 14 Each input circuit has eight screw terminals associated with it
29. RE INSTALLATION Software is not included with the CYEXP GP but each of the data acquisition boards with which it is intended to be used includes software called InstaCal that may be used to aid installation verify operation and perform calibration of the CYEXP GP The disk or CD labeled JnstaCal contains this software package If you ordered the Universal Library you should load InstaCal from that CD or disk set The board has a variety of switches and jumpers to set before installing the board in your computer InstaCal will show you all available options how to configure the various switches and jumpers to match your application requirements and will create a configuration file that your application software and the Universal Library will refer to so the software you use will automatically have access to the exact configuration of the board Please refer to the Software Installation Manual regarding the installation and operation of InstaCal Use InstaCal along with the following hard copy information to set the hardware configuration of the board This page deliberatelyleft blank 3 GENERAL CONFIGURATION 3 1 A D Board Type Select Jumper The CYEXP GP can be used with either DASO8 or DAS16 family boards because the signal assignments of the 37 pin connectors match those of the DASO8 and may be adapted to those of the DAS16 with a CBL MX10 cable Select the A D board type via the JB10 jumper Jumper JB10 on the CYEXP
30. VEXC SEL which stands for channel excitation voltage select This jumper will connect the on board excitation voltage to one of the A D board channels so that it can be measured CyberReseach does not use a measurement of the excitation voltage in any of its software You do not need to set this jumper if you are using the board with CyberResearch software or with packages such as Labtech Notebook which use the Universal Library Use this jumper only with software from other manufacturers that specifically require it 7 3 CJC Jumper Select There is a set of jumpers near the 37 pin connector labeled CJC SEL which stands for cold junction compensation select Remove this jumper There is no cold junction compensation used with bridge sensors 7 4 Powering the CYEXP GP There are two power issues to address The first is the source of the 5 volt power to the board The second is the source of the bridge excitation voltage power 7 4 1 Selecting the Power Source for the Board The General Configuration section describes the power selection options for powering the CYEXP GP itself Configure your boards as described in Powering the CYEXP GP in the General Configuration section before continuing with this section 7 4 2 Selecting the Power Source for the Excitation Voltage Bridge sensors consume a lot of power In some cases the bridge sensors consume so much power that if fully populated with eight sensors the on board excitation c
31. able S17 for X1 or X2 5 Input amplification for EACH CHANNEL is switch selectable CHO through CH7 for X1 X10 X100 or X1000 A user specified gain may be set by supplying a precision resistor at position RX and setting the U option on switch CH to ON 5 5 1 Output Gain Switch There is a switch on DIP switch block S17 Figure 5 5 labeled X1 and X2 5 Sliding this switch down amplifies the output of the multiplexers by 2 5 The factory default position up has a gain of 1 unity Setting the Board Gain The X2 5 gain switch is useful in some thermocouple measurements If you desire a voltage gain of 2 5 25 or 250 set this switch down Recommended gains for thermocouples are between X10 and X200 Figure 5 5 Output Gain Switch Location The effect of this switch is multiplicative with respect to the individual channel gains For example if you have set an input channel gain to X100 and the board output gain to X2 5 the signal is amplified by 250 before it reaches the A D board 5 5 2 Setting the Channel Gain 21 There is a gain switch for each channel Figure 5 6 Set the input channel gain to match the expected voltage output of the bridge you are measuring to the input range of the A D board as described above Channel Gain Switches There is a set of DIP gain switches for each input circuit labeled GAIN Figure 5 6 There are four two position switches for each channel The gain switches are labe
32. al and Precise Stain Based Measurement by James Pierson 1992 400 pages in 3 ring binder ISBN 1 895976 00 6 Available from Society for Experimental Mechanics order JP 001 Strain Gage and Transducer Techniques 1984 72 pages Published by Published by Society for Experimental Mechanics order S 023 Society for Experimental Mechanics 7 School St Bethel CT 06801 203 790 6373 42 EC Declaration of Conformity We the manfacturer declare under sole responsibility that the product CYEXP GP Voltage TC RID and Bridge inputs for ISA bus Part Number Description to which this declaration relates meets the essential requirements is in conformity with and CE marking has been applied according to the relevant EC Directives listed below using the relevant section of the following EC standards and other normative documents EU EMC Directive 89 336 EEC Essential requirements relating to electromagnetic compatibility EU 55022 Class B Limits and methods of measurements of radio interference characteristics of information technology equipment EN 50082 1 EC generic immunity requirements IEC 801 2 Electrostatic discharge requirements for industrial process measurement and control equipment IEC 801 3 Radiated electromagnetic field requirements for industrial process measurements and control equipment IEC 801 4 Electrically fast transients for industrial process measurement and control equipment For your no
33. attenuation by the low pass filter 16 5 CONFIGURATION FOR THERMOCOUPLE MEASUREMENT Thermocouples are temperature sensors constructed of wires of two dissimilar metals fused together at a point This junction of two metals produces a voltage that varies relative to temperature Thermocouple voltages require several manipulations in order to be useful These are 1 A very low voltage is produced and so must be amplified by a factor of between 100 and 1 000 2 The voltage produced by the thermocouple is not linear with respect to temperature so it must be linearized Linearization in this case is calculated by software after the voltage is acquired 3 A voltage producing junction is also created at the screw terminal where the thermocouple is connected to the CCYEXP GP The temperature at this cold junction must be measured and the voltage calculated and subtracted from the total measured from the thermocouple This is also calculated by software The circuit that measures this temperature is the Cold Junction Compensation CJC circuit 4 Thermocouples are subject to EMI and RFI noise due to the very low level of the voltage and the large amplification factor These affects can be reduced through averaging and filtering There is a 70Hz low pass filter on the CYEXP GP Averaging may be done in software Thermocouples are not as accurate as RTDs or other precision temperature sensors but they are much less expensive Sometimes an a
34. beyond the scope of this description These examples can be used to as a guide for calculating the bridge voltage in your own application and thus help you select the proper amplifier gain and excitation voltage The use of quarter bridge half bridge and full bridge strain gauge configurations are described The Application In these examples imagine a beam extending out from a fixed point on a wall Force is applied to deflect the end of the beam downward We know that the maximum strain to be measured will be 250u 250 micro strain Knowing the amount of force required and the size of the beam is not necessary since strain relates to the change in length of the surface of interest The Strain Gauge will be a metal foil type 350 ohms resistance Gauge Factor 2 Refer to the Appendix for information on these specifications The following example shows a bending strain measurement example It can be used to calculate the bridge voltage and thus help the user select the proper amplifier gain and excitation voltage The use of one two and four strain gauges will be examined 35 A Quarter Bridge Example For 1 4 bridge circuits the strain gauge has a single resistive element that is connected as one leg of the bridge The other three legs must be populated with the precision completion resistors EXCITATION VOLAGE EXCITATION VOLTS SENSE LOW EXCITATION VOLTS Null Pot SENSE HIGH TO CHANN
35. d avoid repeated calls Here are a few preliminary actions you can take before you call which may solve some of the more common problems 1 Check the PC bus power and any power supply signals 2 Check the voltage level of the signal between SIGNAL HIGH and SIGNAL LOW or SIGNAL and SIGNAL It CANNOT exceed the full scale range of the board 3 Check the other boards in your PC or modules on the network for address and interrupt conflicts 4 Refer to the example programs as a baseline for comparing code 45 Warranty Notice CyberResearch Inc warrants that this equipment as furnished will be free from defects in material and workmanship for a period of one year from the confirmed date of purchase by the original buyer and that upon written notice of any such defect CyberResearch Inc will at its option repair or replace the defective item under the terms of this warranty subject to the provisions and specific exclusions listed herein This warranty shall not apply to equipment that has been previously repaired or altered outside our plant in any way which may in the judgment of the manufacturer affect its reliability Nor will it apply if the equipment has been used in a manner exceeding or inconsistent with its specifications or if the serial number has been removed CyberResearch Inc does not assume any liability for consequential damages as a result from our products uses and in any event our liability shall not exceed
36. d to measure a change of 1 millivolt you would need an amplification of 10 In order to match your signals with the input range of the A D board you should do a similar calculation and set switches on the CYEXP GP for the required gain Remember to make sure that the settings in InstaCal match the switches on the DAS and CYEXP GP boards If you are measuring signals greater than the maximum full scale range of the A D see the section on attenuation 11 To choose a switch selectable amplification here are the calculations you need to perform Divide the full range selected for the A D board by the full range of the signal to be measured to determine the maximum gain of the CYEXP board For best resolution use the highest gain possible up to the calculated maximum gain For example if the A D board is to be used at a range of 5V the full range of the board is 10 If your signal ranges between 0 5 volts and 0 5 volts the full range of the signal is 1 volt Divide 10 by 1 fora result of 10 That is the maximum gain you can use If your signal is unipolar and ranges less than 0 to 5V you would likely choose the 5V unipolar range for the A D board if available Given an input signal ranging from 0 to 0 5 volts the full range of the signal is 1 2 volt Divide 5 the full range of the A D by 0 5 the full range of the signal for a result of 10 That is the maximum gain you can use 4 4 Setting the Gain Gain amplification allows
37. e Storage Remperature Range Humidity OP07 1 10V 5 mA 25 mA indefinite DC 100 Ohms maximum Output jumper selectable for one of 16 channels P1 amp P2 Output 0 to Output 15 HI508A multiplexer 2N2222 transistor inverter 3 digital inputs for selecting multiplexer channel 1 digital input for controlling calibration relay 0 8V max 4V absolute minimum 1 0V max 4V absolute minimum 2 4V min 9V absolute maximum 1 27V min 9V absolute maximum 10V 4V 2V 1V 0 5V 5V from PC 5V from MOLEX 12V from PC external PEXT screw terminal 100mA 275mA 350mA 670mA Output jumper selectable for one of 16 channels P1 amp P2 Output to Output 15 Voltage adjustable for zero error ImA 8 4 6V typical 2V minimum Adjustable for zero error 24 4mV C OmV 0 C 0 to 60 C 40 to 100 C 0 to 90 non condensing 40 9 APPENDIX 9 1 About Strain Gauges 9 1 1 What Are Strain Gauges A Strain Gauge is a variable resistance device whose resistance changes in proportion to the amount it is stretched or compressed Physically it is an etched metal foil in a grid pattern that is glued to any surface which undergoes strain The output is a dimensionless quantity defined as change in length and whose symbol is A micro strain of 1 means that length of the surface of interest has changed by ppm The ratio of resistance change to strain change is known as the Gauge Factor GF Typical metal foil strain
38. easuring thermocouples two wire measurement should be used Set the two switches labeled 4 on each IN CONFIG Channel Configuration switch to the ON down position for each channel used for thermocouple measurement See IN CONFIG Figure 5 2 on the right S Set the two switches labeled 3 on each IN CONFIG switch for thermocouple channels to the OFF up position Rw Rw CHO CHANNEL CONFIGURATION SWITCH SET FOR THERMOCOUPLES BOTH 4s ARE ON DOWN BOTH 3s ARE OFF UP Figure 5 2 Channel Configuration Switches 5 3 2 Enabling Open Thermocouple Detection OTD Open thermocouple detection OTD is enabled for a channel by installing a resistor and closing the TC pad with a solder bridge see Figures 5 3 and 5 4 There are locations marked TC for each channel for this purpose OTD provides the high side of the thermocouple signal with a reference to SOmVDC at very low current If a thermocouple opens it ceases to produce a voltage If that happens the OTD voltage drives the signal on that channel to full minus Most software is set up to alarm for an open thermocouple when a temperature falls to full scale minus value The CYEXP GP will accurately measure thermocouples without the TC pad closed but you must close it and install a 100K resistor to have OTD 18 Table 5 1 100K ohm Resistors to be Installed for Te Channel 1 RX11 Channel 3 RX 23 sere a 7 Please solder the pads with the solder pr
39. his channel for any of the other boards 3 3 Configuring the A D Board 3 3 1 DAS08 Family Setup The input mode of the A D board must be single ended to be compatible with the CYEXP outputs Some of the boards in the DASO8 series have differential inputs that can be converted to single ended inputs See the information shipped with your A D board for conversion to single ended inputs 3 3 2 DAS16 Family Setup The input mode of the A D board must be single ended to be compatible with the CYEXP outputs Most of the DAS16 series is switch selectable for either 8 differential or 16 single ended inputs When used with the CYEXP set the switch to 16 channel single ended mode 3 3 3 All A D Boards If you are using an A D board with switch selectable ranges consider the application and determine the best fit for range vs expected voltage For example when measuring resistance such that the output of the EXP board is expected to be in the range of 3 to 4 5 volts a unipolar 5V range would be the best choice If the range on your A D board is fully programmable the software you use for measurement will determine the range 3 4 CONNECTING THE CYEXP GP TO THE A D BOARD 3 4 1 Connecting to a DAS08 Series A D Board A CYDAS 8 series board may be connected directly through a CBL 3700 series cable from the P1 connector on the CYEXP GP to the A D analog connector The JB10 jumper should be left in the DASO8 position as set at the factory 3 4
40. in InstaCal match the switches on the DAS and CYEXP GP boards When using strain gauges the expected output from the sensor should be calculated and the gain of the CYEXP GP set accordingly There are some examples at the end of this chapter detailing these calculations You may also find it helpful to refer to the Appendix for additional strain gauge information 7 6 Setting the Gain Once you have determined the gain required for your application set the gain of the CYEXP GP using the following guide Amplification for ALL channels board output gain is switch selectable S17 for X1 or X2 5 Input amplification for EACH CHANNEL is switch selectable CHO through CH7 for X1 X10 X100 or X1000 A user specified gain may be set by supplying a precision resistor at position RX and setting the U option on switch CH to ON 31 7 6 1 Setting the Board Gain There is a switch on DIP switch block S17 Figure 7 3 labeled X1 and X2 5 Sliding this switch down amplifies the output of the multiplexers by 2 5 The factory default position up has a gain of 1 unity The X2 5 gain switch is useful in some voltage and bridge measurements If you desire a voltage gain of 2 5 25 250 or 2500 set this switch down Figure 7 3 Board Gain The effect of this switch is multiplicative with respect to the individual channel gains For example if you have set an input channel gain to X100 and the board output gain to X2 5 the sig
41. ining the Appropriate Gain 000000002 cece ees 31 TG Setn TNE Gain seis teeth aie eh Andale eA e Added ars e Ea etd An EA a ok Ata 31 TOs WS TINE the Board Gam steep er ee ate Slice sem E nt Vote a nea E 32 7 6 2 Setting the Channel Gain 33 55 50 5 4 5 a050 eh we ROG A Rete es 32 7 7 Setting the Input Configuration 00 066 c ccc eee 33 7 8 Configuring the Bridge 9 5 pin spend jee dois eee ane ded Ped eee ROT NS 33 7 8 1 Bridge Completion Resistors ic seedy ey a atone wee key eae aM eeERS 34 7 8 2 Nulling Potentiometers amp Arm Resistor 0 0 cece eee eee ee 35 7 8 3 Strain Gauge Bridge Configuration Examples 0000 cee eae 35 7 9 Verifying the Installation 0 000000 ees 38 S SPECIFICATIONS isis eh ee AA E IG see a REA 39 Ned d d DI DI D 55555 E a TD A Re LA IIS OD ATARI RON OR oe ew 41 9 1 About Strain Gauges 0 e teenies 41 9 1 1 What Are Strain Gauges annnnn ununun anana r oe Mey ea koe Mee eee TRS 41 9 1 2 Specification of Strain Gauges yoke olde okek se Leeaher dh ek ep et weeabie thers 41 9 2 Reference Material for Application of Strain Gauges 41 1 INTRODUCTION The CYEXP GP is an eight channel signal conditioning accessory designed for use with the DAS08 and DAS16 family of data acquisition boards It can condition signals from bridge sensors RTDs or thermocouples on a per channel basis It converts the sensor s outp
42. ion A custom gain may be selected on the CYEXP GP by installing a precision resistor and setting the switch marked U User in the down position See Table 4 1 following for board positions and some sample gain values GAIN FOR CHANNELS 0 and 4 SET FOR A GAIN OF 10 SLIDER DOWN SELECTS GAIN ALL OTHERS TO BE OFF UP Figure 4 2 Input Channel Gain Select Switches Table 4 1 Resistor Positions for User Selected Gains Channel Resistor Position Channel Resistor Position 0 RX100 4 RX104 1 RX101 5 RX105 2 RX102 6 RX106 3 RX103 7 RX107 Gain Resistor Value 50 716 Ohms 100 364 Ohms 200 161 Ohms 500 40 Ohms 700 17 Ohms 800 10 Ohms The equation for selecting the USER gain resistor is Ruser 40000 Gain 1 40 Amplifying a signal on one channel will not affect the reading on another channel 4 5 Attenuation If your signal is in a range greater than the full scale range of the A D you must either set the A D for a higher full scale range if available or divide attenuate the signal until the result is less than or equal to the A D s full scale range This section describes signal attenuation 13 INPUT A voltage divider is constructed from a pair of precision resistors selected according to the equation Volts In OUT Attenuation Ra Rb Rb A See Figure 4 3 at right for the schematic of Rb wel eile a voltage divider M Y
43. ircuit would not have adequate power to 29 supply all eight sensors This is an extreme case but is indicative of the attention you must pay to power requirements when using bridge sensors Also when selecting the power source for the excitation voltage consider the voltage you will use for excitation The options available are 0 5 1 2 4 and 10V In general higher excitation voltages are better because a higher voltage increases the difference between the balance points of the bridge circuit which increases the accuracy of your measurement The excitation voltage must be less than the source Jumper JB11 Figure 7 1 located near the bottom edge of the board mak selects the source of the bridge excitation voltage The three choices are 5V the same 5V source chosen for board power above 12V from the asta a m_a ms PC through the 37 pin connector or PEXT an external power supply 2 connected at the P EXT screw terminal 4 Figure 7 1 Output Gain amp Power Select If you choose a separate power supply it must be a floating isolated supply one with three terminals Do not tie the GND and V terminal together It must not exceed 15V The 5V and 12V jumpers are only valid with CYDAS 8 family boards The 12V jumper is not valid with the CYDAS 8 AO and PGx For more information on excitation voltages refer to the section on bridge sensors 5V Excitation Voltage Source If your choice for the excita
44. istive element usually a length of wire encased in a sheath Various wire materials are used with platinum being the most common There are three types of hookups two wire three wire and four wire An excellent source of information on RTDs and how to select one for your application may be found in the OMEGA Engineering catalog 6 1 Channel Selection The General Configuration section describes the channel selection setting the jumper and verifying the installation and operation of the CYEXP GP with your data acquisition board Configure your boards as described in that section before continuing with this section 6 2 VEXC JUMPER Select There is a set of jumpers near the 37 pin connectors labeled VEXC SEL which stands for channel excitation voltage select These jumpers connect the on board excitation voltage to one of the A D board channels so that it may be measured CyberResearch does not use a measurement of the excitation voltage in any of its software You do not need to set this jumper if you are using the CYEXP GP with CyberResearch software or with packages such as Labtech Notebook which use the Universal Library Use this jumper only with software from other manufacturers that specifically require it 6 3 CJC Jumper Selection There is a set of jumpers near the 37 pin connector labeled CJC SEL which stands for cold junction compensation select Remove this jumper There is no cold junction compensation used with b
45. led U X10 X100 and X1000 Select a gain higher than unity by moving the switch for that gain down All other switches should be left in the UP position GAIN FOR CHANNELS 0 and 4 SET FOR A GAIN OF 10 SLIDER DOWN SELECTS GAIN a ALL OTHERS TO BE OFF UP A custom gain may be selected on the CYEXP GP by installing a precision resistor and setting the switch marked U User in the down position See Table 5 2 below for positions and some sample gain values Figure 5 6 Channel Gain Switches Table 5 2 User Gain Resistors Identities Channel Resistor Position Channel Resistor Position 0 RX100 4 RX104 1 RX101 5 RX105 2 RX102 6 RX106 3 RX103 7 RX107 Gain Resistor Value 50 716 Ohms 100 364 Ohms 200 161 Ohms 500 40 Ohms 700 17 Ohms 800 10 Ohms The equation for selecting the gain resistor is Ruser 40000 Gain 1 40 5 6 Verifying the Installation Your channel is now configured to make thermocouple measurements To verify the installation use the InstaCal program installed on your computer This software came with your A D board if you bought the board from the same manufacturer as the CYEXP GP Use the CALIBRATE option to calibrate the CJC and verify the operation of the channel Use the TEST option to make a measurement in engineering units 22 6 CONFIGURATION FOR RTD MEASUREMENTS An RTD is a temperature sensor that consist of a res
46. nal is amplified by 250 before it reaches the A D board 7 6 2 Setting the Channel Gain There is a gain switch for each channel Figure 7 4 Set the input channel gain to match the expected voltage output of the bridge you are measuring to the input range of the A D board as described above Channel Gain Switches There is a set of DIP gain switches for each input circuit labeled GAIN Figure 7 4 There are four two position switches for each channel The gain switches are labeled U X10 X100 and X1000 Select a gain higher than unity by moving the switch for that gain down All other switches should be left in the UP position GAIN FOR CHANNELS 0 and 4 SET FOR A GAIN OF 10 SLIDER DOWN SELECTS GAIN a ALL OTHERS TO BE OFF UP A custom gain may be selected on the CYEXP GP by installing a precision resistor and setting the switch marked U User in the down position See Table 7 1 below for positions and some sample gain values Figure 7 4 Input Channel Gain Switches 32 Table 7 1 User Specified Gain Resistor Positions Channel Resistor Position Channel Resistor Position 0 RX100 4 RX104 1 RX101 5 RX105 2 RX102 6 RX106 3 RX103 7 RX107 Gain Resistor Value 100 364 Ohms 200 161 Ohms 300 130 Ohms 500 40 Ohms 700 17 Ohms 800 10 Ohms The equation for selecting the gain resistor Rusrr for any gain between X100 and X1000 is Ruser 4000
47. ne the CYEXP GP circuit to your advantage then be sure to update the InstaCal program so the Universal Library linearization routines will operate properly 6 6 Setting the Gain Once you have determined the gain required for your application set the gain of the CYEXP GP using the following guide Amplification for ALL channels board output gain is switch selectable S17 for X1 or X2 5 Input amplification for EACH CHANNEL is switch selectable CHO through CH7 for X1 X10 X100 or X1000 A user specified gain may be set by supplying a precision resistor at position RX and setting the U option on switch CH to ON 6 6 1 Setting the Board Gain There is a switch on DIP switch block S17 Figure 6 1 labeled X1 and X2 5 Sliding this switch down amplifies the output of the multiplexers by 2 5 The factory default position up has a gain of 1 unity The X2 5 gain switch is useful in some voltage and bridge measurements If you desire a voltage gain of 2 5 25 250 or 2500 set this switch down Figure 6 1 Board Gain The effect of this switch is multiplicative with respect to the individual channel gains For example if you have set an input channel gain to X10 and the board output gain to X2 5 the signal is amplified by 25 before it reaches the A D board 25 6 6 2 Setting the Channel Gain Channel Gain Switches There is a set of gain switches for each input circuit Figure 6 2 There are two 4 switch DI
48. nnect one CYEXP GP to another using a CBL 370x ribbon cable Connect from P2 on the upstream board to P1 on the downstream board Make sure each of the boards in the chain have a unique channel selected CH SEL jumper is set to a different number on each board 3 7 Connecting a Test Voltage Make your initial test of the CYEXP GP with a voltage signal of between 5 and 5V If you use an AC signal source keep the frequency below 70 Hz to avoid attenuation by the CYEXP GP s low pass filter Each input circuit has eight screw terminals associated with it These terminals are shown in the diagram to the right To connect a voltage signal to the input circuit you use three screw terminals as follows NOWINOD YO NI SLTIOA INNO NOLLVIIOXd nN x O z Z Q z z G Z n gt s r J NI SLTOA SLTOA NOILYLIOXJ d NI SLTOA SENSE Connect to voltage SENSE Jumper to P INNO NOILV IID Xd P Connect to Ground There is not enough room on the board for the full name tg d I n an next to each terminal so the eight screw terminals a Z x 3 p z ein te Bom A g a a associated with each input circuit are labeled on the j CYEXP QP as follows CHO Figure 3 6 Input Screw Terminals P Excitation voltage SENSE Low side of input SENSE Hardwired to the other SENSE same function IEXC Excitation current return P Excitation voltage return common with IEXC
49. o set any jumpers other than those previously mentioned and should not set any switches or install any passive components until you have verified the installation When using an AC signal source keep the frequency below 70 Hz to avoid attenuation by the low pass filter 10 4 CONFIGURATION FOR VOLTAGE MEASUREMENT The CYEXP GP is an amplification signal conditioning and multiplexing accessory for DAS boards The inputs are suitable for connecting a low frequency voltage to the DAS board so it can be measured The CYEXP GP is a one of eight multiplexer which means that for every channel in your DAS board you can multiplex eight different signals to it You can expand the number of inputs of your DAS board by eight for every CYEXP GP board up to the number of inputs on the DAS board For example a DASO8 has 8 inputs Eight times eight is sixty four Using CYEXP GP boards you can bring 64 inputs into the PC with one DASO8 in one slot It is unlikely that you purchase a CYEXP GP to measure voltages The CYEXP GP has a 70Hz low pass filter and quite a bit of elaborate circuitry designed for bridges TCs and RTD sensors For applications requiring only voltage measurements a CYEXP 16 or CYEXP 32 would be less expensive and do the same job Possibly you have one or two voltages to measure in addition to bridge or RTD sensors and would like to connect those signals to the CYEXP GP 4 1 Channel Selection The General Configuration section desc
50. okup is handy when the signal source is floating with respect to ground such as a battery The floating differential input will reject up to 10V of EMI energy on the signal wires CAUTION Is the signal source really floating Check it with a voltmeter before risking the CYEXP GP and the PC 4 73 Fully Differential A differential signal has three wires from the signal source The signals are Signal High Signal Low and Signal Ground LLGND Signal High is connected to the SENSE terminal and Signal Low is connected to the SENSE terminal The ground reference must be connected to the P terminal A differential connection allows you to connect the CYEXP GP to a signal source with a ground that is different than the PC ground but less than 10V difference and still make a true measurement of the signal For example a laboratory instrument with its own wall plug Sometimes there is a voltage between wall outlet grounds 15 4 8 Verifying the Installation To verify the installation use the InstaCal program installed on your computer This software came with your A D board if you bought the board from the same manufacturer as the CYEXP GP If your A D board is not from the same manufacturer but is compatible please call technical support and request a copy of InstaCal Use InstaCal s TEST option to verify that a signal present at one of the CYEXP GP inputs can be read When using an AC signal source keep the frequency below 70 Hz to avoid
51. onds to one of the 16 pins on the 37 pin connector When the CYEXP GP is connected to a DASO8 only the first 8 channels labeled 0 7 can be used When the CYEXP GP is connected to a DAS16 all 16 jumper positions can be used In each case the jumper corresponds to a channel number on the A D board If the jumper setting does not agree with the selection made in InstaCal setup InstaCal and the Universal Library will not be able to make readings from the CYEXP GP Figure 3 3 is a diagram of the Channel Select jumper There are two other groups of output jumpers similar to this group The top group shown here is marked CH SEL O o2 AG a S OTTAR ISLAS Channel Select the center jumper group is i 0 0oo o ZISIS CH SEL VEXC SEL excitation voltage select and the eoeeeece eeeeeeee bottom group is marked CJC SEL Cold Junction CHANNEL 0 SELECTED Compensation Select FOR SENSOR OUTPUT Figure 3 3 Output Channel Select Jumper Place the jumper on the pin which corresponds to the A D board s input channel Each jumper set must select a unique A D channel For example if you are using the excitation or CJC outputs in addition to the signal output each should be set to a different channel number One individual channel must be selected for each bank of 8 EXP channels For example if you are using several CYEXP GP boards the jumper setting for each board must be unique If you select channel 0 for the first board do not use t
52. ossible gain values Where the output voltage exceeds 5V the reading is clipped Table 5 4 Voltage Output Maximum Temperature Type Output Max C Vout at Max Temp Max x10 X100 X250 X1000 Temp J 42 3mV 750 0 42 4 2 10 6 42 K 50 6mV 1 250 0 51 5 1 12 7 51 T 17 8mV 350 0 18 1 8 4 5 18 E 68 8 900 0 69 6 9 17 2 69 S 15mV 1 450 0 15 1 5 3 8 15 R 16 7 1 450 0 17 1 7 4 2 17 20 Voltages which exceed the 5V range are in bold italics in the table above Table 5 5 shows the temperature at which the reading is clipped the maximum readable temperature for thermocouple types at a given gain Table 5 5 Maximum Readable Temperatures with A D on 5V Range Type Max C Max Readable Temp vs Gain X10 X100 X250 X1000 J 750 750 C 750 C 366 C 95 C K 1 250 1 250 C 1 232 C 484 C 121 C T 350 350 C 350 C 350 C 115 C E 900 900 C 660 C 287 C 80 C S 1 450 1 450 C 1 450 C 1 450 C 576 C R 1 450 1 450 C 1 450 C 1 450 C 548 C From these tables you can determine that if you want to use a J type thermocouple to make a reading of 700 degrees the gain should be set at 100 This yields a resolution of 0 48 degrees C per bit 5 5 Setting the Gain Once you have determined the gain required for your application set the gain of the CYEXP GP using the following guide Amplification for ALL channels board output gain is switch select
53. ovided It has a water soluble flux which should be washed off If you use another type of solder or do not wash off the flux it may affect your readings EXCITATION VOLAGE EXCITATION VOLTS THERMOCOUPLE LEAD SENSE LOW SENSE LOW EXCITATION CURRENT EXCITATION VOLTS THERMOCOUPLE LEAD SENSE HIGH SENSE HIGH TO CHANNEL MULTIPLEXOR 80Hz Low Pass Filter 100K TC PULL 50 mV 10K ws GND REF EXCITATION CURRENT Figure 5 3 OTD and Ground Reference Jumper Pads Schematic NOTE If you want to change the use of the input circuit to an RTD or bridge sensor remove the solder that closes the TC pad and the G pad also Open Thermocouple Detection Jumper Pads Ground Reference Jumper Pada For TC s Only a O HELL pg r s dew gt aS e328 C 99000058 Figure 5 4 OTD and Ground Reference Jumper Pads Locations Typ 19 5 3 3 Adding a Ground Reference The CYEXP GP inputs are fully differential which helps reject noise on thermocouple wires If thermocouples connected to the CYEXP GP inputs are to work properly the G pad must be closed on any channel used for thermocouple measurement see Figures 5 3 and 5 4 The G pad provides a reference from ground to the analog low input via a 10K resistor Only enough current passes through the resistor to provide a reference to ground The analog high and low inputs are still able to float within the
54. r the CYEXP GP through the 37 pin connector by setting the power select switch on S17 to 5 COMP 3 5 3 Powering with the Molex Connector The CYEXP GP can be powered off the PC s power supply by connecting the optional external 5V power connector the Molex connector labeled P19 to the PC s power supply through a C MOLEX 10 cable This cable has the same Molex connector that is used inside the PC and so can be connected directly to the PC s power supply through one of the spare connectors The cable is keyed so it should not be forced When inserted properly it will slide easily and snap in place 3 5 4 Powering Through the Power Screw Terminals A set of screw terminals labeled 5V REM and REM GND are located below the 37 pin connectors P1 and P2 You can power the CYEXP GP from a 5V 45 power supply capable of at least 400 mA For this option set the power select switch on S17 to REM CAUTION Connect the ground of the power supply to the ground of the personal computer with a heavy gauge wire If you do not strap the two grounds together a voltage between these grounds will 8 affect measurements If the potential exceeds the protection range of the input circuits the board may be damaged At this time ignore the other screw terminals located next to the power and ground terminals They are needed only with certain sensors and will be explained in those sections 3 6 Daisy Chaining CYEXP GP Boards Co
55. ribes the channel selection setting the jumper and verifying the installation and operation of the CYEXP GP with your data acquisition board Configure your boards as described in that section before continuing with this section 4 2 Powering the CYEXP GP The General Configuration section describes the power selection options setting the power select switch and verifying the installation and operation of the CYEXP GP with your data acquisition board Configure your boards as described in that section before continuing with this section 4 3 Determining The Appropriate Gain To accurately measure a voltage the full scale of the signal should be matched to the full range of the input circuit Most DAS boards have an input range of 5V which is the native range of the analog to digital converter at the heart of the board Some DAS boards include amplification on the input circuit to allow the signal to be amplified to make better use of the resolution of the A D For example an input signal which varies between O and 1 volt would only be using 1 10th of a 5V A D converter s resolution By switching the input signal of the DAS board to unipolar no negative voltage and amplifying the input signal by 5 the entire range of the A D converter is used and a higher resolution measurement may be made By adding this gain and selecting this range the resolution on a 12 bit A D improves from 2 4 millivolts per bit to 0 24 millivolts per bit If you neede
56. ridge sensors 6 4 Powering the CYEXP GP The General Configuration section describes the power selection options for powering the CYEXP GP itself Configure your boards as described in Powering the CYEXP GP in the General Configuration section before continuing with this section 6 5 Determining the Appropriate Gain To accurately measure a voltage the full scale of the signal should be matched to the full range of the input circuit Most DAS boards have an input range of 5V which is the native range of the analog to digital converter at the heart of the board Some DAS boards include amplification on the input circuit to allow the signal to be amplified to make better use of the resolution of the A D For example an input signal which varies between O and 1 volt would only be using 1 10th of a 5V A D converter s resolution By switching the input signal of the DAS board to unipolar no negative voltage and amplifying the sign wave signal by 5 the entire range of the A D converter is used and a higher resolution measurement may be made By adding this gain and selecting this range the resolution on a 23 12 bit A D improves from 2 4 millivolts per bit to 0 24 millivolts per bit If you needed to measure a change of 1 millivolt you would need an amplification of 10 In order to match your signals with the input range of the A D board you should do a similar calculation and set switches on the CYEXP GP for the required gain Remember
57. t be set to 12V as shown in Figure 7 1 or PEXT S17 Do not select an excitation voltage at the switch that exceeds the excitation power supply voltage a x 2 8 l Nn AOI Nn Q O z gs Figure 7 2 Excitation Voltage Select Switches 7 5 Determining the Appropriate Gain To accurately measure a voltage the full scale of the signal should be matched to the full range of the input circuit Most DAS boards have an input range of 5V which is the native range of the analog to digital converter at the heart of the board Some DAS boards include amplification on the input circuit to allow the signal to be amplified to make better use of the resolution of the A D For example an input signal which varies between 0 and 1 volt would only be using 1 10th of a 5V A D converter s resolution By switching the input signal of the DAS board to unipolar no negative voltage and amplifying the sign wave signal by 5 the entire range of the A D converter is used and a higher resolution measurement may be made By adding this gain and selecting this range the resolution on a 12 bit A D improves from 2 4 millivolts per bit to 0 24 millivolts per bit If you needed to measure a change of 1 millivolt you would need an amplification of 10 In order to match your signals with the input range of the A D board you should do a similar calculation and set switches on the CYEXP GP for the required gain Remember to make sure that the settings
58. te FADE RE IE EARS Roe RAS 23 6 5 Determining the Appropriate Gain 0 000000 23 6 6 Setting the Gain 44 ci0k teniser ties avee dh havekintes peo che e ena eee as 25 6 6 1 Setting the Board Gain yes 64446 8s he ea te Os ee ES ER RS 25 6 6 2 Setting the Channel Gain 2 5 3 5 45 4 lt p dedodee 4nd oe bes dS Pelee dead Gee he ase pe 26 6 7 Input Configuration 0 00 0 aaaeeeaa tte e eben ees 26 6 7 1 Setting the Input Configuration sic iies anes ce canes ve eens ee bie ean 26 6 8 Connecting RTDs To Screw Terminals 0 00 c cece eee 27 6 8 1 Two Wire RTD Hookup iog oh5 5 hie Rh 4 Ge AI Sie ES EARS SEPA es 27 6 8 2 Three Wire RTD Hookup gapeich ce Seed Ke eo ad Dee DOES Re a eRe RRO Rae 27 6 8 3 Four Wire RTD HOOKUP t524 4 paki oy ek chile Win ooh gg a ee Ae wale eed ape e 27 6 9 Verifying the Installation 0000000 eees 28 7 CONFIGURATION FOR RESISTANCE MEASUREMENTS 29 TAM Hanne elec 5 34 ah ca eel esac yh ee Ae le tre SO Neate Beare The 29 12 V EXC Jumper Select oriai ee SAN Wen eh anes ea ie eas 29 7 3 CJC Jumper Select rrr eae ARI ORE RL Re eS 29 7 4 Powering the CYEXP GP 4 ee Vesa todd CAS raare 29 7 4 1 Selecting the Power Source for the Board 0 000 c cece eee ee 29 7 4 2 Selecting the Power Source for the Excitation Voltage 04 29 7 4 3 Selecting the Excitation Voltage lt ys s644c es oe ee ea Roe eo HES 31 7 5 Determ
59. tes 44 Product Service Diagnosis and Debug CyberResearch Inc maintains technical support lines staffed by experienced Applications Engineers and Technicians There is no charge to call and we will return your call promptly if it is received while our lines are busy Most problems encountered with data acquisition products can be solved over the phone Signal connections and programming are the two most common sources of difficulty CyberResearch support personnel can help you solve these problems especially if you are prepared for the call To ensure your call s overall success and expediency 1 Have the phone close to the PC so you can conveniently and quickly take action that the Applications Engineer might suggest 2 Be prepared to open your PC remove boards report back switch or jumper settings and possibly change settings before reinstalling the modules 3 Have a volt meter handy to take measurements of the signals you are trying to measure as well as the signals on the board module or power supply 4 Isolate problem areas that are not working as you expected 5 Have the source code to the program you are having trouble with available so that preceding and prerequisite modes can be referenced and discussed 6 Have the manual at hand Also have the product s utility disks and any other relevant disks nearby so programs and version numbers can be checked Preparation will facilitate the diagnosis procedure save you time an
60. th the precision 350 ohm completion resistors EXCITATION VOLAGE EXCITATION VOLTS SENSE LOW EXCITATION VOLTS Null Pot SENSE HIGH TO CHANNEL MULTIPLEXOR Pass Filter Figure 7 7 2 Bridge Circuit Simplified Schematic Half Bridge Calculations The 1 2 bridge implementation consists of two strain gauges one on the top of the beam as in the 4 bridge example and one on the bottom of the beam The strain gauge on the bottom of the beam replaces completion resistor C in the 4 bridge implementation Two active strain gauge elements one in tension and one in compression result in twice the sensitivity of the bridge One element increases resistance while the second element decreases resistance simultaneously When the beam is forced down 250ue change the resistance in C decreases by 0 175 ohm and resistance A increases by 0 175 ohm as shown in the 1 4 bridge example above The bridge voltage V is then Vor 10V 350 700 350 0 175 350 0 175 350 0 175 Vor 10V 350 700 349 825 700 Voir 2 500mV Choosing Gain X1000 would result in 2 5V being applied to the DAS board Choosing Gain X2500 X1000 on the input channel and X2 5 on the output could result in an amplified voltage that s out of the DAS board s range In this case the excitation voltage could be reduced to 4V reducing the bridge voltage to 1 00mV A gain selection of
61. tion voltage source is 5V you may choose a 0 5V 1V 2V or 4V excitation voltage for your bridge sensors The 5V option is always available since 5V is required to power the CYEXP GP 12V Excitation Voltage Source If your choice for the excitation voltage source is 12V PC power you have the choice of 0 5 1 2 4 or 10 volt excitation for your bridge sensors The option to power from the PC 12 volt supply exists only with DAS08 family boards except that 12V is not valid with the CYDAS 8 AO or PGA PEXT Excitation Voltage Source An external power supply can be used If you choose a separate power supply it must be a floating or isolated supply one with three terminals Do not tie the GND and V terminal together Output voltage must not exceed 15V If your power supply is not floating it is likely that you will create a ground loop current flow in the ground lines A ground loop will induce an error in your reading Connect the power supply to the CYEXP GP at the terminals labeled PEXT and PEXT on the screw terminal block located adjacent to the 37 pin connector P2 30 7 4 3 Selecting the Excitation Voltage DIP switch S17 has five switches to select bridge excitation voltage Only set one ON All others must be OFF LX gt gt Waee gt gt Figure 7 2 shows the switch and the excitation power source jumper set for the factory defaults Excitation is set for 10V ON Power source mus
62. to make sure that the settings in InstaCal match the switches on the DAS and CYEXP GP boards When using RTD s the expected output from the sensor should be calculated and the gain of the CYEXP GP set accordingly To select the best gain for RTD type base resistance and temperature range consider that RTD resistance changes with temperature but the magnitude of the change also changes with temperature RTD type determines the slope of the ohms vs temperature curve The most popular type has an alpha of 00385 known as the European standard Its value is 00385 ohms per ohm per C The Universal Library and InstaCal support six different RTD types Please call if you do not see the RTD you are interested in listed here Material Alpha Platinum 0 00392 American standard Platinum 0 00391 Platinum 0 00385 European standard Most popular OMEGA s standard also Copper 0 00427 Nickel Iron 0 00581 Nickel Iron 0 00527 To determine which gain to use you must know the maximum temperature the RTD will be used to measure and thus the maximum resistance value of the RTD Here is a table for platinum For 100 ohm RTD alpha 00385 Temp C Resistance ohms 200 18 49 100 60 25 0 100 00 100 138 50 200 175 84 300 212 02 400 247 04 At a temperature of 400 C the maximum resistance is 247 04 ohms The equation for the voltage out of the CYEXP GP the voltage your DAS board will convert into a number is
63. ttempt is made to make a measurement beyond the accuracy of the thermocouple such as measuring 1 10th of a degree over the full scale Read the accuracy and repeatability specification of the thermocouple and consider the effects of linearization on the reading before choosing thermocouples The CYEXP GP is not the optimum choice for thermocouple only applications The CYEXP 32 and CYEXP 16 are less expensive and just as accurate for thermocouple measurements The CYEXP GP has extra circuitry devoted to bridge and RTD sensors 5 1 Selecting The Output Channel The General Configuration section describes the channel selection setting the jumper and verifying the installation and operation of the CYEXP GP with your data acquisition board Configure your boards as described in that section before continuing with this section 5 2 Selecting The CJC Output Channel There is a set of jumpers near the 37 pin connectors labeled CJC SEL which stands for cold junction compensation select These jumpers connect the on board measurement of the cold junction temperature to one of the A D board channels for use in temperature calculations The CJC temperature reference is universally used by software to compensate for the voltage induced at the cold junction the screw terminal The software package you are using will determine which channel you need to set this jumper on The default is channel 7 the channel used by default by the Universal Library
64. ut to a voltage suitable for conversion by a DAS08 DAS16 or other analog to digital conversion board This manual is organized into sections that explain the CYEXP GP on a sensor by sensor basis The CYEXP GP is complex and the information on bridge sensors may confuse those interested in RTDs only and vice versa Here are the sections of this manual Software Installation All users should review this section regardless of the application General Configuration All users should review this section regardless of the application Configuration for Voltage Measurement Users interested in voltage measurement applications hould review this section Configuration for Thermocouples Users interested in temperature measurement pplications using thermocouples should review this section Configuration for RTD Measurement Users interested in temperature measurement pplications using RTDs should review this section Configuration for Resistance Measurement Users interested in resistance or strain gauge measurement applications should review this section Please carefully read the installation and general configuration sections and each of the sections pertaining to the sensors you intend to use There are optional resistors jumpers switches and other connections to be made on the CYEXP GP Failure to set up the channels correctly for the sensor in use will result in inaccurate or invalid measurements This page deliberatelyleft blank 2 SOFTWA

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