Temperature Measurements using the KPCI-3108 with the
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1. Channel Range Format Sensor Header 16 1 25t01 25 C ice 17 O1t001V PC K Da N GRR it ge i i i all Al Ready eS renee Notice that channel 16 is DriverLINX input channel for the FWA CJC and channel 17 is input channel for the K type thermocouple The following screen shows the output data in an Excel graph of the K type thermocouple located on software channel 17 As you can see a simple test of room temperature 23 0 5 C was attainable using this free software 147108602583 Note the above data plot does not have any software averaging invoked ExceLINX provides means to use signal averaging ExceLINX for Data Acquistion is a free download from our web site To acquire a free copy go to www keithley com and select Products and go to Software The ExceLINX Help feature can guide you through the use of the software package Conclusion The KPCI 3108 was found to communicate and control an EXP 1800 The KPCI 3108 is an ideal board if one needs to convert an ISA based EXP 1800 system over to PCI If you already own an EXP 1600 with a DAS 1600 card the KPCI 3108 can also be an upgrade path for ISA to PCI bus migration One should always review EXP hardware specifications prior to selecting any new EXP board for your application Keithley EXP models are not uniform in performance or product options One should be aware of these distinctions and always select the appropriate EXP f2. Channel Selection at Position the two instances of AlOPanel side by side so that you can access them both Since the channel select jumper of the EXP 1800 is on channel 0 configure the Meter tab to display channel 0 of the KPCI 3108 board as shown above As discussed earlier the EXP 1800 switches between channels via the digital MUX lines that are provided on the KPCI 3108 card These lines can be software manually selected via the AIO Panel under the DIO Tab The following screen shot shows the DIO Tab The immediate four grayed out bits to the right under the Digital Output Panel corresponds to 0 15 on the EXP 1800 in binary format DriverLINX AIO Panel File Help KEITHLEY Digital lapat Panel Channels Digital Output Panel Output Bits um 4 2 3 A i ae TE KEITHLEY Digital I0 Coafiguratios Panel Channel Configuration Input Output The gain of the EXP 1800 can be controlled by the value of OP4 on the KPCI 3108 OP4 is shown highlighted in green in the Digital Output Panel frame fifth bit to the left When OP4 is logic 1 green the EXP 1800 gain of 50 is invoked When OP4 is logic 0 gray the EXP 1800 is at gain of 1 The screen above shows the DIO tab of AlOPanel Notice that the Digital Output Panel has the DIO channel 0 turned on default bits 0 3 gray and gain of 50 selected by having 4 bit set to logic 1 green light Now command the EXP 1800 to a gain of 1
3. EXP 1800 with a KPCI 3108 Series board the digital output lines OP0 OP4 of the KPCI 3108 board will be set for Enable EXP addressing For calibration change the configuration to General purpose Output use In the DriverLINX Configuration Panel form Start Menu gt Programs gt DriverLINX gt DriverLINX Configuration Panel configure the KPCI 3108 digital output lines OPO OP4 for general purpose Output as shown below This will allow us to have manual control of OP OP4 in the AlOPanel Configure KPCI 3108 Options Ea OP5 Setup IV Enable Bus Mastering TGOUT I Use 8254 Gate for Al C CLKOUTO Digital Output OPO 4 Setup C CLKOUTI General purpose Dutpuk CICS CLKOUT2 C SSH amp CLKOUTs Enable EXP addressing EXPCLKOUT Hep Additionally the analog input channel configuration should always be set for 16 single ended mode as shown below when using EXP 1800 accessories with plug in boards Configure DriverLINX Device x Digital Input Digital Output Counter Timer Device Analog input Analog Output e Interrupt x Range programmable z DMA z level M caiba Channels fynere Cancel Help You will need to reboot to allow these configuration settings to take effect Once the software configuration has been changed we will now need to adjust several hardware potentiometers on the EXP 1800 On the EXP 1800 both the RTO R14 zero adjust and RT
4. 0 with switch cards becomes a more cost effective choice for large channel count applications When using DriverLINX the KPIC 3108 board s single ended native channels are always channels 0 through 15 The EXP 1800 can be used with any of the KPCI 3108 native channels it is not required to begin at channel 0 and increase consecutively for each additional EXP added Figure below shows the EXP 1800 channel assignments for three boards using DriverLINX channel mapping DAS or KPCI board Analog Input Channels when Using DriverLINX Driver In the above diagram the channel numbers assigned to the EXP are different under ASO than they are under DriverLINX Notice that the first software channel begins with channel 16 on the first EXP 1800 assigned to channel 0 of the KPCI 3108 With the following EXP 1800s the channel mapping will be incremented by 16 32 48 and etc Next the CJC source selection can be configured for resident EXP 1800 CJC sensor or an external sensor located on an accessory board called the FWA EXP Setting the S 18 switch to FWA or to SOURCE on the EXP 1800 determines your CJC temperature source The output of the CJC is a 10mV per degree C output When CJC is set to SOURCE the CJC voltage output is sent to the first logical channel of the EXP 1800 form the EXP 1800 CJC sensor If using the FWA EXP CJC sensor the user must physically wire a connection to a screw terminal channel on the FWA EXP board The ex
5. I R13 zero adjust potentiometers need to be adjusted to zero volts in order to get valid temperature readings This is accomplished by shorting CHO HI to CHO LO to GND A of the FWA EXP Then adjusting potentiometer R14 to zero volts for a gain setting of 1 and R13 for zero volts for a gain setting of 50 This will require the use of the Keithley AIO Panel to select the channel and the correct gain settings Also this procedure will require a 5 1 2 DMM or the use of another instance of the AlOPanel Meter tab to validate the zero voltage output of the EXP shorted channel For users who intend to use a5 1 2 digit DMM it will require to a connection to the appropriate screw terminals on the STA 3108 A1 For an EXP 1800 set to native KPCI 3108 board channel 0 the corresponding screw terminal pin 33 CHOOHI and pin 18 AGND is correct locations to hook your DMM The DMM will be able to read the output off the EXP 1800 directly Note the output of the EXP 1800 is a single ended output so the screw terminals selected are a single ended output For users who intend to use the AlOPanel Meter tab Set one AlOPanel instance to the DIO tab and the other instance to the Meter tab as shown below DriverLINX Analog 1 0 Panel File Help Setup Scope Meter SST Level Control DIO KEITHLEY Digital laput Panel Channels DriverLINX Analog 170 Panel File Help j Setup Scope Meter SST Level Control Dio Max 7 8 Pecans cn
6. Place a shorting jumper between CH 0 HI and CH 0 LO on the FWA EXP If the output from the EXP 1800 as seen on your 5 12 digit DMM or on the Meter tab of AlOPanel is not at zero volts adjust R14 for zero volts Command the EXP 1800 to a gain of 50 Place a shorting jumper between CH 0 HI and CH 0 LO on the FWA EXP If the output from the EXP 1800 as seen on your DMM or on the Meter tab of AlOPanel is not at zero volts adjust R13 for zero volts Repeat the above two calibration steps one more time to minimize their interaction All adjustments have now been made The calibration is now finished Note other channels of the EXP 1800 can be selected by manipulating the digital lines OPO OP3 of the KPCI 3108 These four bits can generate 16 unique binary codes corresponding to the 16 channels of the EXP 1800 The converted numeric values correspond to the selected channels of the EXP 1800 Remember to set the digital output lines OPO OP4 of the KPCI 3108 board back to Enable EXP addressing so that the DriverLINX software can automatically control the DIO lines when accessing the channels gain of the EXP 1800 Earlier in the document we had shown the software configuration procedure If the KPCI 3108 is not configured for Enable EXP Addressing the MUX lines to the EXP 1800 will not be accessible by the KPCI 3108 Once adjusted EXP 1800 hardware calibration is now complete and you are ready to take calibrated temperature reading
7. Temperature Measurements using the KPCI 3108 with the EXP 1800 by Andy Toth Keithley Instruments Inc Introduction Many applications require the use of data acquisition hardware to take high channel count temperature measurements The goal of this technical note is to setup a KPCI data acquisition card using an external EXP multiplexing card We will be using a KPCI 3108 as the data acquisition hardware connected to an EXP 1800 as the 16 channel multiplexing card We will be reading in temperature on single channel connected to a standard K type thermocouple While this type of temperature measurement solution for high channel count uses a multiplexing card Keithley offers several other temperature measuring solutions for high channel count that may better fit your application or system platform If your application requires less than 15 channels of temperature measurement Keithley offers an accessory called the STP 36CJC screw terminal panel with a built in CJC sensor for use with KPCI 3108 Series board With other applications limited to 31 channels Keithley offers a one card solution called the KPCI 1801HC used with STA 1800HC screw terminal panel The KPCI 1801HC avoids having to use two EXP 1800s to achieve 31 temperature channels For applications that require thermocouples to be connected at a distance Keithley offers the M 1000 Series modules that can communicate on RS 232 or RS 485 Finally the 2700 2750 2701 data acqui
8. ample found in this document used the FWA approach Connecting the thermocouple hook ups are just to a screw terminal connection on the FWA EXP which is the field wire assembly board that allows for multiple channel hook up of thermocouples the red wire of the thermocouple is always the ground or channel lo connection Note a 10 K bleed resistor to Low Side Bias Return to GND A is provided via Switch 3 on the DIP switch settings for channels CHO CH15 on the EXP 1800 Activating this setting will improve your thermocouple input readings for thermocouple lead lengths that may be subjected to static or EMI interference Other signal conditioning settings will not be covered in this document The EXP 1800 has variety of settings for Low Pass Filter 80 Hz Open Thermocouple Detect and Ground Selection It is highly recommended that you review this section on the Low Pass Filter in the EXP 1800 User s manual A Low Pass Filter may help eliminate 60 Hz power line noise in some laboratory or production floor environments Calibration One of the most critical requirements in temperature measurement is the calibration of your instrument or in this application your devices The EXP 1800 has some very critical set points that need to be adjusted in order to make your temperature readings correct and within product specification The following paragraphs will discuss the calibration procedure of an EXP 1800 while using the KPCI 3108 O
9. ftware Installation The software installation requires the loading the Windows based driver software called DriverLINX The install procedure for DriverLINX will not be covered in this document Please reference the DriverLINX install sheet that is shipped with the KPCI 3108 card as a source of reference Once the KPCI 3108 card has been successfully installed with DriverLINX it will require a special driver configuration modification in the DriverLINX Configuration Panel folder located on your desktop Start gt Programs gt DriverLINX gt DriverLINX Configuration Panel Select the Configure command button when DeviceO of the KPCI 3108 is highlighted reverse blue in the DriverLINX Configuration Panel This will bring up the Configure DriverLINX Device dialog box shown below Configure DriverLINX Device Digital Input Digital Output Counter Timer Device AnalogInput Analog Output Vendor Keithley Instruments Inc Device jo Model Board Id 00811627 M Detect Dec 7 Calibrate Hex id __ Special At this time you can verify that your board analog inputs are set to 16 single ended Just go to the Analog Input tab and verify the board Channels are set to 16 single ended Note the EXP 1800 requires this configuration setting Usually the default DriverLINX driver configuration setting will be set to 16 single ended mode Configure DriverLINX Device B xi Digital Input Digital Output Cou
10. ing up the EXP 1800 signal cable to a KPCI 3108 card requires the additional support of the STP 3108 A1 screw terminal panel along with the following cables CAB 1284CC and the CACC 2000 The screw terminal panel is just a transition device to map the KPCI 3108 signals to and from the EXP 1800 Note users should be using the most recent product revision STP3108A1 102 02C of the screw terminal panel which enables support for the EXP 1800 product line The correct screw terminal panel will have the 02C designator along with the part number located on the product Note Earlier revisions may not report correct readings with your setup Connecting power to the EXP 1800 you will need to set the switch S 9 of the EXP 1800 to PWR SEL and NOT to the DAS BOARD The KPCI 3108 does not provide for external power and the use of an external power supply is required to power the EXP 1800 The required Keithley power supply part number is PWR 5V for the EXP 1800 Setting the EXP 1800 channel mapping requires that you select the appropriate channel on the KPCI 3108 to map the expanded channels Setting jumper to CHO on the J2 connector of the EXP 1800 allows for this mapping to occur on the KPCI 3108 hardware through channel 0 All the EXP 1800 channels will pass through channel 0 of the KPCI 3108 Expanded channel mapping allows for additional 15 more EXP 1800s to be connected to a KPCI 3108 card for a total of 256 temperature signals model 2700 or 275
11. n existing DAS 1800 ISA based EXP 1800 system over to a KPCI 3108 PCI based EXP 1800 system For new applications the KPCI 1801HC PCI product line offers up to 32 channels of temperature inputs native to the board without the need of an external EXP 1800 card System Verification System verification requires testing your hardware with some type of application software Unfortunately the AlO Test Panel in DriverLINX will not suffice when it comes to temperature conversion and reporting However Keithley offers a free software plug in called ExceLINX for Data Acquisition This software package works with MS Excel 97 or greater It allows for quick verification of temperature readings by capturing and converting data into an Excel spread sheet This is an ideal tool for users who do not need a custom software application that requires advanced features Note ExceLINX for Data Acquisition has a sister package called ExceLINX 1A for Instruments which offers the same flexibility for the 2700 2750 temperature measuring instrument line with built in added features Below is screen shot displaying the ExceLINX software working with the EXP 1800 The image below shows the configuration of an ExceLINX s Al Pace Clock Analog Thermocouple input task X Microsoft Excel Book1 E 18 xj Is File Edit View Insert Format Tools Data ExceLINX Window Help lal x a A Sl A amp B Z ly Bl 100 amp z8 O F Bigs E tes os Ae
12. n the Keithley website www keithley com there is an EXP 1800 calibration software that is a useful tool in calibrating your EXP 1800 The software can be found under Application Technical Support under Software Downloads using EXP 1800 as the keyword Below is a screen shot of the calibration utility that is a VB6 application with source code available to calibrate an EXP 1800 while using a KPCI 3108 along with DriverLINX This utility greatly simplifies the calibration procedure and automates the process NY EXP 1800 Calibration 10 xj KEITHLEY A Greater Measure of Confidence Enter Device Number 0 5 0 Put EXP 1800 channel select jumper J2 in chan 0 position Apply a shorting jumper between chan 0 HI and chan 0 LO on the FwA EXP Adjust the pots until the reported values are near to zero volts Adjust R14 for Zero test gain of 1 Adjust R13 for Zero test gain of 50 In the above calibration utility program all one has to do is follow the above procedure and adjust the R14 and R13 gain pots on the EXP 1800 See the EXP 1800 hardware manual for gain pots location and description If you prefer to manually calibrate the card with out using the above application software The following paragraphs will discuss a manual approach to calibration by using the AlOPanel as the software control DIO tab and read out Meter tab ora 5 digit DMM instrument as an optional read out method During normal operation of an
13. nter Timer Device Analog Input Analog Output Interrupt v DMA level Channels RSS Erne Bange oroqrammable y JV Calibrate Now go back to the Device tab You will need to select the Special command button in the lower right hand corner of the above window This will bring up the Configure KPCI 3108 Options dialog box that lists all the special hardware feature of the KPCI 3108 card Configure KPCI 3108 Options W x OP5 Setup V Enable Bus Mastering TGOUT Use 8254 Gate for Al C CLKOUTO Digital Output OPO 4 Setup ee C General purpose Output CLKOUT2 C SSH amp CLKOUTs Ene EP siei C BecLKouT Heb Enable EXP addressing radio button shown above This will allow the DriverLINX driver to access the extended channel mapping of the EXP 1800 card s via a four digital lines control that is simply called MUX lines Select OK and close out of the DriverLINX Configuration Panel and reboot your PC in order for the current changes to take effect with the software driver This concludes the software configuration of the KPCI 3108 for the EXP 1800 Hardware Configuration The hardware configuration requires hooking up appropriate signal and power cables interfacing screw terminal panel to the EXP 1800 and then adjusting the proper switch settings located on the EXP 1800 The following paragraphs will be a users guide through the hardware configuration Hook
14. or your intended application After running the ExceLINX for Data Acquisition program under WindowsMe it was determined that we were able to acquire a temperature readings of K type thermocouple at room temperature within a range of 23 0 5 C A similar application example was developed in Visual Basic and similar results were found to be independent of the programming language The benefits for a proprietary programming language is that it allows for customization and flexibility of your software application Some canned software packages like our ExceLINX software have inherent built in limitations due to Microsoft s software design of Excel For VB and C programmers Keithley provides the software algorithm tools to convert raw thermocouple voltages over to temperature Check out the free T C Library COM Object DLL Interface for Thermocouple Linearization package under Software Products at www keithley com
15. s The card will report back thermocouple readings with very little inherent voltage offset If the EXP 1800 is not correctly calibrated the temperature data will be erroneous Remember that thermocouple voltages are on the magnitude of 1 mV and have a sensitivity of approximately 10 micro volts per degree C Even small voltage will influence your thermocouple readings significantly A shorted channel test can isolate whether your system is inherently noisy or if there exists a considerable offset calibration error with the EXP 1800 For the KPCI 3108 card it has its own KPCI 3108 Calibration Utility that guides you through the software calibration process This utility is self guided software application which helps guide through calibration process Note not having both the KPCI 3108 and the EXP 1800 in calibration may cause a substantial voltage offsets on the level of several micro volts or more which may influence your temperature readings Always validate your system with a known voltage standard prior to using the KPCI 3108 card with any thermocouples A six digit calibrated voltage source is highly recommended for a standard Keithley offers several types of instruments that can provide a reliable voltage standard for you to calibrate your system Application A typical application is high channel count measurement of temperature using a standard PC as your mathematical processing device with a KPCI 3108 card or alternatively converting a
16. sition instrument offers the most cost effective solution for channel counts in excess of 31 or applications that demand measurement precision better than 0 5 deg C Setup Prior to any set up using the KPCI 3108 with an EXP 1800 users should have read and became familiar with both the hardware manuals for the KPCI 3108 Series PCI Data Acquisition Board s User s manual P N 98080D and the EXP 1800 User s Guide manual P N 92160A This will ensure that users can follow up on specific topics that will not be covered fully in this document The below block diagram shows a typical KPCI 3108 card with multiple EXP 1800 set up attached in a daisy chain fashion Channel Expansion EXP 1800 connection Up to 16 EXP 1800s are supported per STA 3108 Al1 KPCI 3107 KPCI 3108 When using the EXP 1800 either a PWR 5V 120VAC source or PWR 5V E 230VAC source must be used in conjunction with a PG408A DC DC converter i EXP 1800 CAB 50 1 0 5 The above diagram does not show that each EXP 1800 requires a PG 408A DC to DC converter attached to the EXP 1800 and the required power hook up to the PWR 5V power supply Note when using multiple EXP 1800s they require an additional power jumper cable called the CAB PWR that enables bussing additional power to each EXP 1800 from the same supply This power jumper cable has been omitted in the above diagram Again this is covered in detail in the EXP 1800 Users manual So
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