AI 225 User Manual.book - United Electronic Industries
Contents
1. Thermocouple Temperature 100 Points Type Range P p Noise C RMS Noise C B 0 50 0 16 C 0 24 0 07 E Full 0 06 0 02 J Range 0 07 0 02 K of 0 10 0 03 N Thermocouples 0 12 0 03 R 0 32 0 1 S 0 37 0 1 Tel 508 921 4600 www ueidaq com Vers 3 6 Date August 2009 File Al225Chapter1 fm 7 1 6 Data Represen tation Volts V Copyright 2009 United Electronic Industries Inc DNx Al 225 Analog Input Layer Chapter 1 Introduction Additional factors e Open TC detection circuitry on the DNA STP AI U adds 15uV 2uV constant offset on all channels May be compensated using the CJC temperature sensor calibration Channel channel difference may be adjusted using the offset calibration simod 3 command e CJC sensor is calibrated to better than 0 2 C accuracy at room temper ature e Stays within 0 4 C accuracy from 20 to 75 C temperature The Al 225 layer is equipped with 25 24 bit A D converters The layer can return 24 bit two s complement data in 32 bit words combined with levels on general purpose digital I O lines By default if acquisition is not running the output buffer is filled with relative addresses On reset every entry in the output buffer is filled with its relative posi tion number As an initializing step you should read the buffer and discard the data before proceeding with normal data collection If you start receiving consecutive data fro2. sssessss 3 1 3 Pinout Diagram of the Al 225 Layer sssssssssssssses eene eene emnes 4 1 4 Recommended Ground Connections for Analog Inputs sse 5 1 5 Analog Input Configuration RTD and Bridge Wiring eseee 6 RM M MR M M M M M M UUR Copyright 2009 Tel 508 921 4600 www ueidaq com Vers 3 6 pned Elecronieindusties Ing Date August 2009 File Al 225 User ManualLOF fm 8 a DNx Al 225 Analog Input Layer Chapter 1 1 Introduction Chapter 1 Introduction This document outlines the feature set and describes the operation of the DNx Al 225 Analog Input boards The DNA version is designed for use with a PowerDNA Cube data acquisition system The DNR version is designed for use with a DNR 12 RACKtangle or a DNR 6 HalfRACK system Both versions are functionally identical 1 1 Organization This PowerDNx Al 225 User Manual is organized as follows of this Introduction Manual This chapter provides an overview of PowerDNA Analog Input Series board features the various models available and what you need to get started The Al 225 layer This chapter provides an overview of the device architecture connectivity and logic of the Al 225 layer Programming with the High Level API This chapter provides an
3. 0 00 eee eee eee eee 10 2 1 Creating a Session zi co RE weed Wes Ate vts eu ead ede Tie eL qe aoe raga 10 2 2 Configuring the Channels liliis en 10 2 2 1 Voltage Measurement liiis es 10 2 2 2 Thermocouple Measurement 000 20 e eee less 10 2 2 3 RED Measurement 1 hice uke ce eel eae beefed ag het sale It EAR RI Rag 11 2 3 Configuring the Timing 0 cee nee 12 2 4 Reading Data oou eB Rex RR RR E aed ett eel 12 2 5 Cleaning up the Session lsseeeeeeeeeee e he 12 Chapter 3 Programming with the Low Level API seen 13 3 1 Configuration Settings lilii nen 13 3 2 Channel List Settings 0 0 00 cece lee 14 3 3 Layer specific Commands and Parameters 2000 cee eters 14 3 4 Using the Layer in ACB Mode coc sso pasis panso retris npea eh 15 3 5 Using Layer in DMap Mode ssssssseee eR eh 17 Appendices 1 csse eene ce e Ro afar ela e RUE ae rca ADR n a cn wx n E cal p ad e e cR 19 A SAACCOSSOFLIGS 1a ibo wt bre pb OM bibe pb eee pde tu 19 B Protection Circuits se ae e a E a a ll m mh 19 2 d EI 20 Copyright 2009 i Tel 508 921 4600 www ueidaq com Vers 3 6 pned Elecronieindusties Ing Date August 2009 File Al 225 User ManualTOC fm Table of Figures Chapter T Introduction ieee i E a E E ee 1 1 1 Block Diagram of the DNx Al 225 Layer ssssssssseeeee eene 3 1 2 Photos of DNR and DNA AI 225 Analog Input Layer Boards
4. This section describes how to program the PowerDNA cube using the low level API The low level API offers direct access to PowerDNA DAQBios protocol and also allows you to directly access device registers We recommend that you use the UEIDAQ Framework see Chapter 2 because it is easier to use You should only need to use the low level API if you are using an operating sys tem other than Windows 3 1 Settings Configuration Configuration setting are passed in DqgCmdSetCfg and DqAcbInitOps functions Note that not all configuration bits apply to Al 225 layer The following bits make sense define DQ FIFO MODEFIFO 2L lt lt 16 continuous acquisition with FIFO define DQ LN MAPPED 1L lt lt 15 For WRRD DMAP devices define DQ LN STREAMING 1L lt lt 14 For RDFIFO devices stream th FIFO data automatically For WRFIFO do NOT send reply to WRFIFO unless needed define DQ LN IRQEN 1L 10 enable layer irqs define DQ LN PTRIGEDGE1 1L lt lt 9 stop trigger edge MSB define DQ LN PTRIGEDGEO 1L lt lt 8 stop trigger edge 00 software 01 rising 02 falling define DQ LN STRIGEDGE1 1L 7 start trigger edge MSB define DQ LN STRIGEDGEO 1L lt lt 6 sta
5. Product Disclaimer WARNING DO NOT USE PRODUCTS SOLD BY UNITED ELECTRONIC INDUSTRIES INC AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS Products sold by United Electronic Industries Inc are not authorized for use as critical components in life support devices or systems A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness Any attempt to purchase any United Electronic Industries Inc product for that purpose is null and void and United Electronic Industries Inc accepts no liability whatsoever in contract tort or otherwise whether or not resulting from our or our employees negligence or failure to detect an improper purchase Table of Contents Chapter1 Introduction 0 0 ce ee 1 1 1 Organization of this Manual 00 0 en 1 1 2 Al 225 Layer Features 2 0 lisse pr ee 2 1 3 Device Architecture errari eee ha 3 1 4 Layer Connectors and Wiring 0 0 0 cece eee ee 4 1 4 1 Analog Input Ground Connections 0 0000 e eee eee 5 1 5 Layer Capabilities cette rere arms hne ede ete eee 7 1 5 1 Thermocouple Measurement 0000 00 eee eee eee 7 1 6 Data Representation 00 000 cee tees 8 1 6 1 Software Calibration of this Layer 0 0 0 auaa aaaea 9 Chapter 2 Programming with the High Level API
6. United Electronic Industries The High Performance Alternative DNA DNR AI 225 Analog Input Layer User Manual Simultaneous Sampling 24 bit 25 channel Analog Input Layer for the PowerDNA Cube and RACKtangle chassis August 2009 Edition Version 3 6 PN Man DNx AI 225 0809 Copyright 1998 2007 United Electronic Industries Inc All rights reserved No part of this publication may be reproduced stored in a retrieval system or transmitted in any form by any means electronic mechanical by photocopying recording or otherwise without prior written permission Information furnished in this manual is believed to be accurate and reliable However no responsibility is assumed for its use or for any infringements of patents or other rights of third parties that may result from its use All product names listed are trademarks or trade names of their respective companies See UEI s website for complete terms and conditions of sale http www ueidaq com company terms aspx Contacting United Electronic Industries Mailing Address 27 Renmar Avenue Walpole MA 02081 U S A For a list of our distributors and partners in the US and around the world please see http www ueidaq com partners Support Telephone 508 9214600 Fax 508 668 2350 Also see the FAQs and online Live Help feature on our web site Internet Support Support support ueidaq com Web Site www ueidag com FTP Site ftp ftp ueidaq com
7. DNx Al 225 Analog Input Layer Chapter 3 Programming with the Low Level API 18 SS0I N i DQ ACB DATA RAW 1 uint32 ioffset i DqDmapInitOps pBcb DqeSetEvent pBcb DO eDataAvailable DQ ePacketLost DQ el STEP 4 Start operation DqeEnable TRUE amp pBcb 1 FALSE STEP 5 Process data while keep looping DqeWaitForEvent amp pBcb 1 if event prin for tf Nndata i 0 i lt CHANNELS printf 308x STEP 6 Stop operation DgeEnable FALSE amp pBcb 1 FALSE STEP 7 Clean up DqDmapDestroy pBcb DqStopDQEngine pDqe DqCloseIOM hd0 ifndef WIN32 DqCleanUpDAOQLib fendif FALSE tsin amp DQ eDataAvailable BufferError DQ ePacketOOB timeout amp eventsin i uint32 ioffset i r Copyright 2009 United Electronic Industries Inc Tel 508 921 4600 Date August 2009 Vers 3 6 Al225Chapter3 fm www ueidaq com File DNx Al 225 Analog Input Layer Appendices A Accessories The following cables and STP boards are available for the Al 225 layer DNA CBL 62 2 5ft 62 way round shielded cable DNA STP AI U Universal PowerDNA Universal Analog Input Screw Terminal Panel DNA STP 62 62 channel screw terminal panel DNA 5B CONN 24 channel signal conditioning mating panel B Protection At times the signal being measured appears to clip when attempting to mea Circui
8. dealing with AI 201 device dquser initialize acb structure Now call the function ret DqgAcbInitOps bcb amp Config Copyright 2009 f Tel 508 921 4600 www ueidaq com Vers 3 6 Viited Elecrontc industries Ine Date August 2009 File Al225Chapter3 fm DNx Al 225 Analog Input Layer Chapter 3 16 Programming with the Low Level API 0 TrigSize NULL pDQSETTRIG TrigMode SECICIK 0 loat fCVClk amp CLSize CL 0 uint32 ScanBlock amp acb printf Actual clock rate f n CVCLk Now set up events DqeSetEvent bcb DQ eFrameDone DQ ePacketLost DO eBufferError DQ ePacketOOB STEP 3 Start operation Start operations DqeEnable TRUE amp bcb 1 FALSE STEP 4 Process data We will not use event notification at first just retrieve scans while keep looping DqeWaitForEvent amp bcb 1 FALSE EVENT TIMEOUT amp events if events amp DQ eFrameDone minrq acb framesize avail minrg while TRUE DqAcbGetScansCopy bcb data acb framesize acb framesize amp size amp avail samples size CHANNELS for i 0 i lt size CHANNELS i fprintf fo Sf t float data i if i CHANNELS CHANNELS 1 fprintf fo Xn printf eFD d scans received d samples min d avail d n size samples minrq avail if avail lt minrq break SSS SSS SS SS SS SS SS SS ES See
9. eet Copyright 2009 l Tel 508 921 4600 www ueidaq com Vers 3 6 United Electronic Industries Inc Date August 2009 File Al225Chapter3 fm DNx Al 225 Analog Input Layer Chapter 3 17 Programming with the Low Level API STEP 5 Stop operation DqeEnable FALSE amp bcb 1 FALSE STEP 6 Clean up DgAcbDestroy bcb DqStopDQEngine pDqe DqCloseIOM hd0 ifndef WIN32 DqCleanUpDAQLib endif 3 5 Using Layer in DMap Mode include PDNA h STEP 1 Start DQE engine ifndef WIN32 DqInitDAQLib endif Start engine DqStartDQEngine 1000 10 amp pDqe NULL open communication with IOM hd0 DqOpenIOM IOM_IPADDRO DQ UDP DAQ PORT TIMEOUT DELAY amp DQRdCfg Receive IOM crucial identification data DqCmdEcho hd0 DQRdCfg for i 0 x DQ MAXDEVN i if DORdCfg devmod i printf Model x Option x n DQRdCfg gt devmod i DORdCfg option i else break STEP 2 Create and initialize host and IOM sides DqDmapCreate pDqe hd0 amp pBcb UPDATE PERIOD amp dmapin amp dmapout Copyright 2009 f Tel 508 921 4600 www ueidaq com Vers 3 6 Piited Elecrontc industries Ine Date August 2009 File Al225Chapter3 fm STEP 3 Add channels into DMap i 0 i lt CHANNELS i DqDmapSetEntry pBcb DEVN amp ioffset i printf offset d or Ox x n i DQ_
10. overview of the how to create a ses sion configure the session for analog input and interpret results on the Al 225 series layer Programming with the Low Level API This chapter describes low level API commands for configuring and using the Al 225 series layer Appendices This appendix provides a list of accessories available for Al 225 layer s and a description of protection circiuts Index This is an alphabetical listing of the topics covered in this man ual Conventions To help you get the most out of this manual and our products we use the follow ing conventions Tips are designed to highlight quick ways to get the job done or to reveal good ideas you might not discover on your own CAUTION Caution advises you of precautions to take to avoid injury data loss and damage to your boards or a system crash Text formatted in bold typeface generally represents text that should be entered verbatim For instance it can represent a command as in the following exam ple You can instruct users how to run setup using a command such as setup exe Copyright 2009 i Tel 508 921 4600 www ueidaq com Vers 3 6 Viited Elecrontc industries Ine Date August 2009 File Al225Chapter1 fm DNx Al 225 Analog Input Layer Chapter 1 Introduction 1 2 Al 225 Layer The Al 225 layer has the following features Features s 25 A D simultaneously sampling converters with differential inputs 24 bit resolution 1 25V input rang
11. The idea of layer calibration is to read average and store readings from all channels at zero volts and then at the fixed level 1V is the default level By subtracting actual readings at zero volts from the ideal value 0x800000 straight binary the software calculates calibration offsets The firmware then subtracts the offset adjusting value from the average value read at 1V The result represents an offset compensated reading at 1V By divid ing actual calibration voltage by offset compensated reading the software cal culates the actual channel gain When DQE opens the IOM it automatically downloads calibration coefficients from each Al 225 in the PowerDNA cube by issuing DOCMD RDFIFO commands with FIFO GET CAL FIFO channel In return the firmware sends a CALSET 225 structure which contains the gain calibration level and the averaged readings at zero volts and that level Then the software stores offset adjusting values directly and calculates actual gain for every channel as follows cfvolt cvolt ONEVOLTINNV for all channels gain i cfvolt pcval i You need to perform data calibration only when you configure and use the Al 225 layer directly without DQE running poA DL D o T Copyright 2009 i Tel 508 921 4600 www ueidaq com Vers 3 6 pnited Elegmontc industiies Ing Date August 2009 File Al225Chapter1 fm a a S a S a S ES e S DNx Al 225 Analog Input Layer Chapte
12. a Session 10 E ding etd eading Data D RTD Measurement 11 Data Representation 8 S E Sampling Rate 2 ET Protection 2 Software Calibration 9 Support ii Features 2 T G Thermocouple Measurement 7 Gains 7 Ground Connections 5 ee en PUPPI RUP PUR ee Copyright 2007 Tel 508 921 4600 www ueidaq com Vers 3 6 Unitediclecironie Industries Ine Date August 2009 File Al 225 User ManuallX fm n sv
13. built in CJC sensor session CreateTCChannel pdna 192 168 100 2 Dev0 Ai0 1 100 0 100 0 UeiThermocoupleTypeK UeiTemperatureScaleCelsius UeiCJCTypeBuiltIn Qo e SS UeiAIChannellInputModeDifferential 2 2 3 RTD RTD measurements are configured using the Session object method Measurement CreateRTDChannel RTD sensors are resistive sensors whose resistance varies with temperature Knowing the resistance of an RTD we can calculate the temperature using the Callendar Van Dusen equations RTD sensors are specified using the alpha a constant It is also known as the temperature coefficient of resistance which defines the resistance change factor per degree of temperature change The RTD type is used to select the proper coefficients A B and C for the Callendar Van Dusen equation which is used to convert resistance measurements to temperature To measure the RTD resistance we need to know the amount of current flowing through it We can then calculate the resistance by dividing the measured voltage by the known excitation current To measure the excitation current we measure the voltage from a high precision reference resistor whose resistance is known The reference resistor is built into the terminal block if you are using a DNA STP AI U but you can provide your own external reference resistor if you prefer In addition you must configure the RTD type and its nominal resis
14. e e Bipolar range 1 25V Aln and Aln within 0 25V 5 0V Unipolar range 0 25V 1 25V Aln connected to AGND directly or via up to 10KOhm resistor Input underrange overrange over the 1 25V range is detected by the software and reported 5 S s to 1000 S s per channel sampling rates gt 120dB rejection of AC component of 50 60Hz for sampling rates below 10Hz gt 120dB Power Supply rejection ratio Typical 120dB of common mode rejection 120Hz 3dB analog front end bandwidth 15V overvoltage and 2kV ESD protection at every input One channel may be used for Cold Junction Compensation CJC Entire analog front end isolated from digital circuitry Direct Inputs for thermocouples May be used with RTDs may be used with external excitation source voltage excitation is available on the STP AI U Strain gauge bridge completion resistors required Input Impedance 100 Mohm Input bias current 15nA Non linearity 3ppm 0 000396 System noise 0 5uV RMS at 5Hz acquisition rate Effective number of bits 23 5 5Hz down to 19 1kHz Input ground to system ground isolation 350V me Power consumption 3 9W max SYNC interface option allows external triggering Copyright 2009 i Tel 508 921 4600 www ueidaq com Vers 3 6 pnited Elegmontc industiies Ing Date August 2009 File Al225Chapter1 fm 2 DNx Al 225 Analog Input Layer Chapter 1 3 Introduction 1 3 Device Figure 1 1 is a block diagram of the architecture o
15. f the Al 225 layer Architecture Control Logic Control Logic 32 bit 66 MHz bus Analog Input Connector Optical Isolation External Clocks and Triggers Figure 1 1 Block Diagram of the DNx Al 225 Layer As shown in Figure 1 1 the Al 225 layer has an independent converter for each of the 25 channels A differential input signal goes first to an auto zero buffer amplifier with 125Hz 3dB bandwidth and then to an A D converter The A D converter accepts signals within a 0 25 to 5V range and measures up to a 1 25V difference between AIN and Aln This mode is called referenced bipolar differential because both Aln and Aln are referenced to system ground The Al 225 uses sigma delta A Ds that sample analog signals at 1 8MHz with a high over sampling ratio and pass this data into decimating FIR filters The over sampling ratio varies from 64 to 32768 for various sampling rates This inter working of A D converters allows the Al 225 to deliver true 24 bit resolution at a 5Hz data output rate down to 19 bit resolution at a 1 kHz rate Figure 1 2 Photos of DNR and DNA AI 225 Analog Input Layer Boards Copyright 2009 Tel 508 921 4600 www ueidag com vors 3 6 United Electronic Industries Inc Date August 2009 File Al225Chapter1 fm DNx Al 225 Analog Input Layer Chapter 1 Introduction 1 4 Layer The DNA AI 225 layer supports referenced differential inputs only Both signal Connectors and return line of t
16. he differential signal pair must have a potential within the and Wiring range 0 25V to 5V relative to isolated ground AGND level Figure 1 3 illus trates the pinout of the Al 225 DB 62 female 62 pin connector DIOO AGND 9V 20mA AIN1 AINO Return AINO AIN2 Return AIN2 AIN1 Return AIN4 AIN3 Return AIN3 AIN5 Return AIN5 AIN4 Return AIN7 AIN6 Return AIN6 AIN8 Return AIN8 AIN7 Return AIN10 AIN9 Return AIN9 AIN11 Return AIN11 AIN10 Return AIN13 AIN12 Return AIN12 AIN14 Return AIN14 AIN13 Return AIN16 AIN15 Return AIN15 AIN17 Return AIN17 AIN16 Return AIN19 AIN18 Return AIN18 AIN20 Return AIN20 AIN19 Return AIN22 AIN21 Return AIN21 AIN23 Return AIN23 AIN22 Return AGND AIN24 Return AIN24 DIO2 AGND 9V 20mA RESERVED RESERVED DIO1 RESERVED RESERVED 21 1 42 62 43 Figure 1 3 Pinout Diagram of the Al 225 Layer Copyright 2009 Tel 508 921 4600 www ueidag com vors 3 6 United Electronic Industries Inc Date August 2009 File Al225Chapter1 fm DNx Al 225 Analog Input Layer Chapter 1 5 Introduction 1 4 1 Analog Input To avoid errors caused by common mode voltages on analog inputs follow the Ground recommended grounding guidelines in Figure 1 4 below Connections Type of Input Floating Grounded Input Typical Signal Sources Typical Signal Sources Configuration Thermocouples Instruments or sensors DC Voltage Sources with non isolated outputs Instruments or sensors
17. ing rate for a different channel program the proper decimators in the FIR unit 3 2 Channel List The Al 225 layer has a very simple channel list structure as shown in the table Settings below Bit Name Purpose 31 DQ LNCL NEXT Tells firmware there is a next entry in the channel list 20 DO LNCL TSRO Request timestamp as a next data point 7 0 Channel number 3 3 Layer Layer specific functions are described in the DaqLibHL h file Mrd js DaAdv225Read and This function works using underlying DgReadAIChannel but converts the data using internal knowledge of the input range and calibrates every channel It Parameters Uses pocMD IOCTL with DOTOCTL CVTCHNL under the hood When this function is called for the first time the firmware stops any ongoing operation on the device specified and reprograms it according to the channel list supplied This function uses the preprogrammed CL update frequency 13 75Hz You can reprogram the update frequency by calling DqCmdSetcC1k after the first call to DgAdv225Read Therefore you cannot perform this function call when the layer is involved in any streaming or data mapping operations If you specify a short timeout delay this function can time out when called for the first time because it is executed as a pending command and layer programming takes up to 10ms Once this function is called the layer continuously acquires data and every cal
18. l to learn how to use the other timing modes session ConfigureTimingForSimpleIO 2 4 Reading Reading data from the Al 225 is done using a reader object There is a reader Data object to read raw data coming straight from the A D converter There is also a reader object to read data already scaled to volts or temperatures The following sample code shows how to create a scaled reader object and read samples Create a reader and link it to the session s stream CueiAnalogScaledReader reader session GetDataStream read one scan the buffer must be big enough to contain one value per channel double data 2 reader ReadSingleScan data 2 5 Cleaning up The session object cleans itself up when it goes out of scope or when it is the Session destroyed However to reuse the object with a different set of channels or parameters you can also clean up the session manually session CleanUp SSS SSS ES SS A SS SS 1c o D J ittL i Cp pm a eet Copyright 2009 i Tel 508 921 4600 www ueidaq com Vers 3 6 Viited Elecrontc industries Ine Date August 2009 File Al225Chapter2 fm n Chapter 3 DNx Al 225 Analog Input Layer Chapter 3 Programming with the Low Level API Programming with the Low Level API
19. l to the function returns the latest acquired data If you want to cancel ongoing sampling call the same function with OxFFFFFFFF as a channel number Copyright 2009 i Tel 508 921 4600 www ueidaq com Vers 3 6 Viited Elecrontc industries Ine Date August 2009 File Al225Chapter3 fm DNx Al 225 Analog Input Layer Chapter 3 15 Programming with the Low Level API 3 4 Using the The following is a pseudo code example that highlights the functions needed in Layer in ACB sequence to use ACB on the 225 layer A complete example with error checking Mode can be found in the directory SampleACB205 include PDNA h unit configuration word define CFG225 DQ LN ENABLED DQ_LN ACTIVE V DO LN GETRAW V DQ LN IRQEN DQ LN CLCKSRCO DO LN STREAMING DQ AI225 MODEFIFO uint32 Config CFG225 STEP 1 Start DQE engine ifndef WIN32 DqInitDAQLib endif Start engine DqStartDQEngine 1000 1 amp pDqe NULL Open communication with IOM hd0 DqOpenIiOM OM PADDRO DO UDP DAQ PORT TIMEOUT DELAY amp RdCfg Receive IOM crucial identification data DqCmdEcho hd0 DQRdCfg Set up channel list for n 0 n lt CHANNELS n CL n n l STEP 2 Create and initialize host and IOM sides Now we are going to test device DqAcbCreate pDqe hd0 DEVN DO SSOIN amp bcb Let s assume that we are
20. m the layer such as 0 1 2 it means that either the layer is not initialized properly or it is damaged The following definition converts raw data from the converter into a 24 bit straight binary value define LT2440 GETVAL V V 55 amp Oxffffff 0x800000 To convert data into floating point use the following formula V is a result from the DO LT2440 GETVAL macro 2 5V 2 24y 14 25V Raw 32 bit data received from converter is represented as Reset Bit Name Description State 31 EOC Zero if conversion is completed 0 30 DMY _ Always low 0 29 SIG Sign bit of the conversion If Vy is gt O this bit is NA HIGH If Vix is lt 0 this bit is LOW 28 MSB Most significant bit of the result If both Bit 29 NA and Bit 28 are HIGH the differential input voltage is above FS If both Bit 29 and Bit 28 are LOW the differential input voltage is below FS 27 5 LSB Less significant bits of the result NA 5 3 SubLSB Sub LSB of the result beyond 24 bit level Can NA be used in averaging 1 DIO2 Level of DIO1 line output 1 DIO1 Level of DIO1 line input 0 0 DIOO Level of DIOO line input Tel 508 921 4600 www ueidaq com Vers 3 6 Date August 2009 File Al225Chapter1 fm 8 DNx Al 225 Analog Input Layer Chapter1 9 Introduction 1 6 1 Software Unlike most PowerDNA layers the Al 225 relies on software calibration on the Calibration of host side this Layer
21. on object s method CreateAlChannel is used to configure the chan nel list gain and signal referencing mode The gain and input mode parameters are ignored when using an Al 225 because it doesn t have programmable gain and is differential only Configure session to acquire from channels 0 and 1 session CreateAIChannel pdna 192 168 100 2 Dev0 A10 1 2 2 2 Thermocouple Measurement Copyright 2009 United Electronic Industries Inc 0 15 0 15 UeiAIChannellInputModeDifferential The Al 225 offers very good accuracy thanks to its 24 bit A D converters and its dedicated channel for measuring the Cold Junction Compensation temperature sensor Therefore it is well suited for measuring temperature with thermocou ples Use the session object s method CreateTCChannel to configure the channels thermocouple type CJC sensor and temperature scale You can use thermocouples of type E J K R S T Bor N Tel 508 921 4600 www ueidaq com Vers 3 6 Date August 2009 File Al225Chapter2 fm DNx Al 225 Analog Input Layer Chapter 2 11 Programming with the High Level API You can measure the CJC temperature either by using a sensor integrated in the terminal block or by specifying a constant You can measure temperature in degrees Celsius Fahrenheit Kelvin or Rank ine Configure the session to acquire temperatures in degrees Celsius from channels 0 and 1 using K thermocouples Use the
22. r 2 10 Programming with the High Level API Chapter 2 Programming with the High Level API 2 4 Creating a Session 2 2 Configuring the Channels This section describes how to program the PowerDNA AI 225 using the UEIDAQ s Framework API Since the UEIDAQ Framework is object oriented its objects can be manipulated in the same manner from various development environments such as Visual C Visual Basic or LabVIEW Although the following section focuses on the C API the concept is the same no matter what programming language you use Please refer to the UEIDAQ Framework User Manual for more information on using other programming languages The Session object controls all operations on your PowerDNA device The first task therefore is to create a session object as follows CUeiSession session Framework uses resource strings to select which device subsystem and chan nels to use within a session The resource string syntax is similar to a web URL lt device class gt lt IP address gt lt Device Id gt lt Subsystem gt lt Channel list gt 2 2 4 Voltage Measurement For PowerDNA the device class is pdna To program the analog input circuitry configure the channel list using the session s object method CreateAlChannel For example the following resource string selects analog input channels 0 2 3 4 on device 1 at IP address 192 168 100 2 pdna 192 168 100 2 Dev1 A10 2 3 4 The sessi
23. rt trigger edge 00 software 01 rising 02 falling define DQ LN CVCKSRCI 1L 5 CN clock source MSB define DQ LN CVCKSRCO 1L 4 CV clock source 01 SW 10 HW 11 EXT define DQ LN CLCKSRCI 1L 3 CL clock source MSB define DQ LN CLCKSRCO 1L 2 CL clock source 01 SW 10 HW 11 EXT define DQ LN ACTIVE 1L 1 f STS LED status define DQ LN ENABLED 1L 0 enable operations For streaming operations with hardware clocking select the following flags DO LN ENABLE DO LN ACTIVE DQ LN CVCKSRCO DQ LN ENABLE DQ LN CVCKS base DQ Copyright 2009 United Electronic Industries Inc LN ACTIVE Tel 508 921 4600 Date August 2009 DO LN STR www ueidaq com EAM NG DQ LN IRQEN enables all operations with the layer RCO selects the internal channel list clock CL source as a time The Al 225 supports CV clock is needed to switch on the STS LED on the CPU layer Vers 3 6 File Al225Chapter3 fm 13 DNx Al 225 Analog Input Layer Chapter 3 14 Programming with the Low Level API You can select either the CL or CV clock as a timebase Because of the parallel architecture of Al 225 layer either clock triggers all converters Aggregate rate Per channel rate Number of channels Acquisition rate cannot be selected on per channel basis To select a different result
24. tance at 0 Celsius as shown in the following example Add 4 channels 0 to 3 to the channel list and configure them to measure a temperature between 0 0 and 200 0 deg C The RTD sensor is connected to the DAQ device using two wires the excitation voltage is 5V and the reference resistor is the 20kOhms resistor built into the DNA STP AI U The RTD alpha coefficient is 0 00385 the nominal resistance at 0 Co 2s 100 Ohms and the measured temperature will be returned in degrees Celsius MySession CreateRTDChannel pdna 192 168 100 2 dev0 Ai0 3 0 1000 0 UeiTwoWires Copyright 2009 i Tel 508 921 4600 www ueidaq com Vers 3 6 Viited Elecrontc industries Ine Date August 2009 File Al225Chapter2 fm DNx Al 225 Analog Input Layer Chapter 2 12 Programming with the High Level API 5503 UeiRefResistorBuiltIn 20000 0 UeiRTDType3850 100 0 UeiTemperatureScaleCelsius UeiAIChannellInputModeDifferential 2 3 Configuring You can configure the Al 225 to run in simple mode point by point or buffered the Timing mode ACB mode In simple mode the delay between samples is determined by software on the host computer In buffered mode the delay between samples is determined by the Al 225 on board clock The following sample shows how to configure the simple mode Please refer to the UEIDAQ Framework User Manua
25. tronic Industries Inc DNx Al 225 Analog Input Layer Chapter 1 Introduction The Al 225 layer is capable of acquiring analog input voltages in 1 25V range with gains of 1 at up to 24 bits of dynamic resolution 222nV RMS resolution The layer is capable of generating its own CL channel list clock and trigger and deriving them from either local external lines from its connector or from the SYNCx bus Table 1 1 Gains Card Al 225 Gain Range 1 V1 25 Noise LSB 1 5 Resolution noise limited 222nV The analog RC anti aliasing filtering is tuned to provide roll off at 1 5kHz half of the maximum sampling frequency as shown in Table 1 2 below Table 1 2 Anti Aliasing Filter Parameters Oversampl Noise ENOBs Frequency ing Ratio ADC System ADC System 1000 128 3 5uV 5yV 20 18 800 256 2uV 3uV 21 3 21 400 512 1 40 V 2uV 21 8 21 200 1024 1uV 1 5yuV 22 4 22 100 2048 750nV 1uV 22 9 22 50 4096 510nV 900nV 23 4 23 25 8192 375nV 700nV 24 24 10 16384 250nV 600nV 24 4 24 Thermocouple The AI 225 is capable of performing thermocouple measurements within 0 02 C at 10Hz per channel The higher the speed of measurement the more noise can be expected The following table shows test results for noise for the Al 225 when used in con junction with the STP AI U terminal 10Hz channel acquisition speed
26. ts sure what appear to be normal voltages Clipping is a sign of tripping the pro tection circuitry of the layer which is designed to protect layer components from damage by high voltage This can happen under a variety of conditions such as a different potential for the Al 225 s ground vs the chassis of the instrument this can be fixed by connecting the chassis to the AGND line on the STP AI U Given the variables Let Veg OV this is AGND Let Vcc 5V or anywhere between 4 75V to 5 25V depending on the P S U Breaking the following rules activates the protection circuitry 1 Vcc 0 25V gt Vin gt Veg 0 25V Vec 0 25V gt Vin gt Veg 0 25V 2 Vin Vin lt 1 25V Copyright 2009 i Tel 508 921 4600 www ueidaq com Vers 3 6 United Electronic Industries Inc Date August 2009 File AI225Appx fm Index A H A D Converters 2 High Level API 10 A D Resolution 2 l Accessories 19 Internet Support ii Anti Alias Filtering 7 L Architecture 3 Layer Commands and Parameters 14 B Low Level API 13 Block Diagram 3 M C Mailing Address ii Calibration 9 Mode Capabilities 7 ACB 15 Channel List Settings 14 DMap 17 Channel List Structure 14 oO Cleaning up the Session 12 Organization 1 Configuration Bits 13 Overvoltage Protection 2 Configuration Settings 13 P Configuring Channels 10 Pinout 4 Configure Timing io Product Disclaimer ii Connectors end Winng d Protection Circuits 19 Conventions 1 Creating
27. with isolated outputs DNA STP 37 STP AI DNA STP AI U sea e Ein Differential Two resistors 10k R 100k provide Add this connection to ensure that both grounds are at the same potential return paths to ground for bias currents NOT RECOMMENDED DNA STP AI U Single Ended Ground Referenced Figure 1 4 Recommended Ground Connections for Analog Inputs Because all analog input channels in Al 201 202 207 208 225 layers are isolated as a group you can connect layer AGND to the ground of the signal source and eliminate the resistors shown in Figure 1 4 for floating differential input signals Copyright 2009 Tel 508 921 4600 www ueidaq com Vers 3 6 United Electronic Industries Inc Date August 2009 File Al225Chapter1 fm DNx Al 225 Analog Input Layer Chapter 1 6 Introduction For RTD and Bridge Wiring refer to Figure 1 5 DNA STP 96 or DNA STP AI U 5V 20k ONLY e ie i o w OAInxX 1 TD i OAlnX AGND Figure 1 5 Analog Input Configuration RTD and Bridge Wiring NOTE For more detail on RTD and thermocouple measurement connections refer to the User Manual for the STP AI U Screw Terminal Panel which may be downloaded at www ueidaq com Copyright 2009 f Tel 508 921 4600 www ueidaq com Vers 3 6 pned Elecronieindusties Ing Date August 2009 File Al225Chapter1 fm 1 5 Layer Capabilities 1 5 1 Measurement Copyright 2009 United Elec
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