National Instruments SCXI manual

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Table of contents for the manual

  • Page 1

    SCXI TM SCXI-1141/1142/1143 User Manual SCXI-1141/1142/1143 User Manual May 2007 371748E-0 1[...]

  • Page 2

    Support Worldwide Technical Support and Product Info rmation ni.com National Instruments Corporate Headquarters 11500 North Mopac Expressway Aust in, Texas 78759-3504 USA Tel: 512 683 0100 Worldwide Offices Australia 1800 300 800, Austria 43 662 457990-0, Belgium 32 (0) 2 757 0020, Brazil 55 11 3262 3599, Canada 800 433 3488, China 86 21 5050 9800,[...]

  • Page 3

    Important Information Warranty The SCXI-1141, SCXI-1142, and SCXI-1143 modules are warranted ag ainst defects in materials and workmans hip for a period of on e year from the date of shipment, as evidenced by receipts or other document ation. Nation al Instruments wi ll, at its option, repair or replace equipment that proves to be defective during [...]

  • Page 4

    Conventions The follo wing con v entions are used in this manual: < > Angle brackets that cont ain numbers s eparated by an ellipsis represent a range of v alues associated with a bit or signal name—for example, AO < 3 . . 0 > . » The » symbol leads you through nested menu items and dial og box options to a final action. The sequenc[...]

  • Page 5

    © National Instrument s Corporation v SCXI-1141/ 1142/1143 U ser Manual Contents Chapter 1 About the SCXI-1141/1142/1143 What You Need to Get Started .............. .............. ........... ............ .............. ........... .......... 1-2 National Instruments D ocumentatio n ............... ........... ............ .............. .........[...]

  • Page 6

    Contents SCXI-1141/1142/1 143 User Manual vi ni.com Chapter 4 Theory of Operation Power-Up State ................. ........... .............. ........... .............. ............ .............. ........... ...... 4-1 Digital Control Circuitry .......... ........ ............ ........... .............. ........... ............ ........... ...... [...]

  • Page 7

    Contents © National Instruments Corporation vii SCXI -1141/1142/ 1143 User Manual Appendix B Removing the SCXI-1141/1142/1143 Module Appendix C Common Questions Glossary Index Figures Figure 2-1. Ground-Referenced Signal Conn ectio n................ ............................. .... 2-4 Figure 2-2. Floating Signal Connection ................. ...[...]

  • Page 8

    Contents SCXI-1141/1142/1 143 User Manual viii ni.com Tables Table 1-1. Accessories Available for the SCXI-1141/1142/1143 .............. ............ 1-4 Table 2-1. Front Signal Pin Assignments ...... ...... ........... ........... ............... ........... ... 2-2 Table 2-2. Rear Signal Pin Assignments ....... ......... .............. ..........[...]

  • Page 9

    © National Instruments Corporation 1-1 SCXI -1141/1142/ 1143 User Manual 1 About the SCXI-1141/1142/1143 This chapter describes the SCXI-1141/1142/11 43 module, and explains how to install and remove the hardw are and software. The SCXI-1141/11 42/1143 module has eight lowpass f ilters and eight differential-input amplifiers. The SCXI-1141 has ell[...]

  • Page 10

    Chapter 1 About the SCXI-1141/1 142/1143 SCXI-1141/1142/1 143 User Manual 1-2 ni.com What Y ou Need to Get Started To set up and use the SCXI-1141/1142/ 1143 module, you need the following: ❑ Hardware – SCXI-1141/1142/114 3 module – One of the following terminal blocks: • SCXI-1304 • SCXI-1305 – An SCXI chassis or PXI/SCXI combination c[...]

  • Page 11

    Chapter 1 About the SCXI-1141/1142/1143 © National Instruments Corporation 1-3 SCXI -1141/1142/ 1143 User Manual DAQ . Select the appropriate informat ion for you r application in the remaining drop-down menus and click Go . National Instruments Documentation The SCXI-1141/1142/1143 User Manual is one piece of the documentation set for data acquis[...]

  • Page 12

    Chapter 1 About the SCXI-1141/1 142/1143 SCXI-1141/1142/1 143 User Manual 1-4 ni.com • The follo wing help file for software information: – Start»Programs»National Instruments»NI-DAQ» NI-DAQmx Help Installing Application Software, NI-DAQmx, and the DAQ Device Refer to the DAQ Getting Started Guide packaged with the NI-DAQmx software to inst[...]

  • Page 13

    Chapter 1 About the SCXI-1141/1142/1143 © National Instruments Corporation 1-5 SCXI -1141/1142/ 1143 User Manual V erifying the SCXI-1141/1142/1143 Installation in Software Refer to the SCXI Quick Start Guide for inform ation on verifying the SCXI installation. Installing SCXI Chassis an d Modules in Software Refer to the SCXI Quick Start G uide f[...]

  • Page 14

    Chapter 1 About the SCXI-1141/1 142/1143 SCXI-1141/1142/1 143 User Manual 1-6 ni.com • If you get a Verify SCXI Chassis message box showing the SCXI chassis model number, Chassis ID: x , and the message Slot Number: x Configuration has modu le: SCXI- XXXX or 1141/1142/1143, hardware in chassis is: SCXI- YYYY , 1141/1142/1143 , or Empty , complete[...]

  • Page 15

    © National Instruments Corporation 2-1 SCXI -1141/1142/ 1143 User Manual 2 Connecting Signals This chapter describes input and output sign al connections to the SCXI-1141/1142/114 3 module through the fron t and rear signal connectors. Caution Connections that exceed any of the maximum ratings of input or output si gnals on the SCXI-1141/1142/ 114[...]

  • Page 16

    Chapter 2 Connecti ng Signals SCXI-1141/1142/1 143 User Manual 2-2 ni.com Table 2-1. Front Signal Pin Assignments Front Connect or Diagram Pin Number Column A Column B Column C 32 AI 0 + NC AI 0 – 31 NC NC NC 30 AI 1 + NC AI 1 – 29 NC NC NC 28 A GND NC A GND 27 NC NC NC 26 AI 2 + NC AI 2 – 25 NC NC NC 24 AI 3 + NC AI 3 – 23 NC NC NC 22 A GN[...]

  • Page 17

    Chapter 2 Connecting Signals © National Instruments Corporation 2-3 SCXI -1141/1142/ 1143 User Manual Front Connector Si gnal Descriptions Analog Input Channels The SCXI-1141/1142/1143 module instrumentation amplifiers can reject any common-mode voltage withi n their common-mode inp ut range caused by ground-potential differences between the si gn[...]

  • Page 18

    Chapter 2 Connecti ng Signals SCXI-1141/1142/1 143 User Manual 2-4 ni.com analog ground. The inputs are protect ed against maximum input voltages of up to ±15 V po wered of f and ±30 V po wered on. Caution Exceeding the differential or common-mode input v oltage limit s distorts input signals. Exceeding the maximum common-mode input voltage ratin[...]

  • Page 19

    Chapter 2 Connecting Signals © National Instruments Corporation 2-5 SCXI -1141/1142/ 1143 User Manual Figure 2-2 illustrates how to connect a non-referenced (floating) signal source to an SCXI channel. Figure 2-2. Floating Signal Connection For A C-coupled signals, connect an ex ternal resistor from the A C-coupled input channel to ground. This pr[...]

  • Page 20

    Chapter 2 Connecti ng Signals SCXI-1141/1142/1 143 User Manual 2-6 ni.com Figure 2-4. Ground Offset AC-Coupled Signal Connection Figure 2-5. Floating AC-Coupled Signal Connection Digital Input and Output You can use the EXT CLK input pin on the front connector of the SCXI-1141/1142/114 3 module to control filter cutoff frequency for special purpose[...]

  • Page 21

    Chapter 2 Connecting Signals © National Instruments Corporation 2-7 SCXI -1141/1142/ 1143 User Manual Rear Signal Connector Note If you use the SCXI-1141/1142/1143 module with a National Instruments DA Q device and SCXI cable assembly , you do not need to read the remainder of this chapter . If you also use the SCXI-1180 feedthro ugh pa nel, the S[...]

  • Page 22

    Chapter 2 Connecti ng Signals SCXI-1141/1142/1 143 User Manual 2-8 ni.com T able 2-2 shows the pin assignments for the SCXI-1141/ 1142/1143 module rear signal connector . Pins without signal labels are not connected. Table 2-2. Rear Signal Pin Assignments Rear Connector Diagram Signal Name Pin Number Pin Numb er Signal Na me NC 1 2 NC AI 0 + 3 4 AI[...]

  • Page 23

    Chapter 2 Connecting Signals © National Instruments Corporation 2-9 SCXI -1141/1142/ 1143 User Manual In parallel output mode, chan nel 0 is selected at the out put multiplexer and is connected to AI 0. The se ven othe r channels are directly connected to AI 1 through AI 7, respectively , on the rear connect or . In multiplexed mode, the AI 0 sign[...]

  • Page 24

    Chapter 2 Connecti ng Signals SCXI-1141/1142/1 143 User Manual 2-10 ni.com The signals on the rear signal connect or are classif ied as analog output, digital I/O, or timing I/O signals. 26 SER D A T OUT P0.4 Out put Serial data out—th is signal taps into the SCXIbus MISO line to accept serial output data from a module. 27 DAQ D * / A P0.1 Input [...]

  • Page 25

    Chapter 2 Connecting Signals © National Instruments Corporation 2-11 SCXI-1141/114 2/1143 User Manual Analog Output Signal Connections Pins 3 through 17 of th e rear signal connector are analog out put signal pins. Pin 3 is the main output, and pin 4 is its reference signal. All eight channels are multiplexed onto this output wh en the module is s[...]

  • Page 26

    Chapter 2 Connecti ng Signals SCXI-1141/1142/1 143 User Manual 2-12 ni.com The digital output signal is pin 26. Pin 26 is SER DA T OUT and is equiv alent to the SCXIb us MISO serial data output line. The digital I/O signals of the SCXI-1141/11 42/1143 module correspond to the digital I/O lines of an E/M Series D A Q device. T able 2-4 lists the equ[...]

  • Page 27

    © National Instruments Corporation 3-1 SCXI -1141/1142/ 1143 User Manual 3 Configuring and T esting This chapter discusses configuring the SCXI-1141/1142/1143 in MAX using NI-DAQmx, creating and testing a virtual channel, glob al channel, and/or task. Notes NI recommends that you ha v e NI-D A Qmx 8.3 or later installed . Refer to the SCXI Quick S[...]

  • Page 28

    Chapter 3 Configur ing and T esting SCXI-1141/1142/1 143 User Manual 3-2 ni.com Input Selection The front end of the SCXI-1141/1142/ 1143 includes a software configurable switch that allows you to program matically connect the inpu t channels of the SCXI-1141/1142/114 3 to either the front connector or internal ground. Refer to Table 5-1, NI-DAQmx [...]

  • Page 29

    Chapter 3 Configurin g and T esting © National Instruments Corporation 3-3 SCXI -1141/1142/ 1143 User Manual NI-DAQmx Using NI-DAQmx, you can configure software settings, such as sensor type and gain/input signal range, in the following ways: • T ask or global channel in M AX • Functions in your application Note All software-configurable setti[...]

  • Page 30

    Chapter 3 Configur ing and T esting SCXI-1141/1142/1 143 User Manual 3-4 ni.com 6. If you are creating a task, you can se lect a range of channels by holding do wn the <Shift> key while select ing the channels. Y ou can select multiple individual channels by holding do wn the <Ctrl> key while selecting channels. If you are creat ing a c[...]

  • Page 31

    Chapter 3 Configurin g and T esting © National Instruments Corporation 3-5 SCXI -1141/1142/ 1143 User Manual 4. Select the channel(s) you want to v erify . Y ou can select a block of channels by holding down the <Shift> ke y or multiple channels by holding down the <Ctrl> key . Click OK . 5. Enter the appropriate information on the Set[...]

  • Page 32

    © National Instruments Corporation 4-1 SCXI -1141/1142/ 1143 User Manual 4 Theor y of Operation This chapter contains an ov erview of the SCXI-1141/1142/1143 module and explains the operation of each functional unit of the module. The SCXI-1141/1142/1 143 module has eight software-controlled input channels that amplify and f ilter signal s. Each c[...]

  • Page 33

    Chapter 4 Theory of Operation SCXI-1141/1142/1 143 User Manual 4-2 ni.com Figure 4-1. SCXI-11 41/1142/1143 Module Block Diagram External Clock Analog Bus Rear Signal Connector Analog Switch Analog Switch Digital Interface and Control Filter Input Protection F ront Signal Connector SCXIbus Connector Calibration Selection + – Instrumentation Amplif[...]

  • Page 34

    Chapter 4 Theory of Operation © National Instruments Corporation 4-3 SCXI -1141/1142/ 1143 User Manual Digital Control Circuitr y The digital control circui tr y contains a Module ID (i dentification) register, a configuration register for the m odule, a gain register, and an EEPROM for storing gain-calibration constants. The Module ID register co[...]

  • Page 35

    Chapter 4 Theory of Operation SCXI-1141/1142/1 143 User Manual 4-4 ni.com In general, to provide optimum measurement resolution and noise rejection, you can select as high a g ain as will not cause the output to exceed this limit. Howe ver , total harmoni c distortion (THD) increases at higher output lev els, especially at h igher input frequencies[...]

  • Page 36

    Chapter 4 Theory of Operation © National Instruments Corporation 4-5 SCXI -1141/1142/ 1143 User Manual Lowpass Filters The SCXI-1141/1142/1143 module filters are 8th-order elliptic, Bessel, and Butterworth lo wpass filters, respec tively. These filter s are a hybrid of a switched-capacitor and a con tinuous-time architecture, th us providing good [...]

  • Page 37

    Chapter 4 Theory of Operation SCXI-1141/1142/1 143 User Manual 4-6 ni.com As Figure 4-2b sho ws, a real f ilter has ripple (an uneven v ariation in attenuation versus frequency) in the passband, a transition region between the passband and the stopband, and a stopband with finite attenuation and ripple. In addition, real filters have some nonlinear[...]

  • Page 38

    Chapter 4 Theory of Operation © National Instruments Corporation 4-7 SCXI -1141/1142/ 1143 User Manual As Figure 4-4 sho ws, the SCXI-1141/1142/1143 module provides 80 dB attenuation abov e 1.5 times the cu tof f frequenc y for the SCXI-1141 module, six times for the SCXI-1142 module, and 3.2 tim es for the SCXI-1143 module. The SCXI-1141, whi c h[...]

  • Page 39

    Chapter 4 Theory of Operation SCXI-1141/1142/1 143 User Manual 4-8 ni.com Figure 4-5. T ypical Passband Re sponses of the SCXI-1141/1142/1143 Module Phase Response Figures 4-6 thro ugh 4-8 i llustrate the ph ase response characteristics of the SCXI-1141/1142/114 3 module filters. Figure 4-6 shows the phase shift as a function of frequency (norm ali[...]

  • Page 40

    Chapter 4 Theory of Operation © National Instruments Corporation 4-9 SCXI -1141/1142/ 1143 User Manual Figure 4-6. Phase Response Characterist ics of the SCXI-1141/1142/1143 Module Filters Figure 4-7 shows the adv a ntages of the SCXI-1142 Bessel f ilter . The Bessel filter is designed for constant group delay at the expense of passband gain and s[...]

  • Page 41

    Chapter 4 Theory of Operation SCXI-1141/1142/1 143 User Manual 4-10 ni.com Figure 4-7. Ph ase Error of the SCXI-1141/1142/1143 Module The most common effect of phase nonlinearity is ringing in response to a step input. As Figure 4-8 shows, the SC XI-1141 elliptic filter exhibits the most overshoot and ringing and the SCX I-1142 Bessel filter has no[...]

  • Page 42

    Chapter 4 Theory of Operation © National Instruments Corporation 4-11 SCXI-1141/114 2/1143 User Manual Figure 4-8. Unit Step Response of the SCXI-1141/1142/1143 Module Setting the Cutoff Frequency The cutoff frequencies of the filters in the SCXI-1141/1142/114 3 module are set internally by dividing a base frequency of 100 kHz by an integer. You c[...]

  • Page 43

    Chapter 4 Theory of Operation SCXI-1141/1142/1 143 User Manual 4-12 ni.com than the signal frequency range of interest. At frequencies much lo wer than the cutof f f requenc y , passband r ipple and phase nonlinearity are much less noticeable. If you use the filter to pre vent alias ing, you must set the cutoff frequency no higher than one-third of[...]

  • Page 44

    Chapter 4 Theory of Operation © National Instruments Corporation 4-13 SCXI-1141/114 2/1143 User Manual Because the SCXI-1141 module stopba nd begins at 1.5 times the cutof f frequency , the Nyquist frequency should be at least 1.5 times the cutoff frequency . Thus, the rate at which the D A Q de vice samples a channel should be at least three time[...]

  • Page 45

    Chapter 4 Theory of Operation SCXI-1141/1142/1 143 User Manual 4-14 ni.com Using the External Clock Input You can set the cutoff frequencie s of filters in the SCXI-1141/1142/11 43 module by using the external cl ock input in applications th at require external control of th e cutoff frequency or th at require finer resol ution than the module prov[...]

  • Page 46

    Chapter 4 Theory of Operation © National Instruments Corporation 4-15 SCXI-1141/114 2/1143 User Manual For bes t results, the cutof f frequenc y of a particul ar f ilter should rem ain within this range. If the cuto f f fr equency goes abov e this range, the prefilters and postfilters interfere with signals in the passband, causing additional atte[...]

  • Page 47

    Chapter 4 Theory of Operation SCXI-1141/1142/1 143 User Manual 4-16 ni.com Filter Bypass Mode You can bypass the fil ter of any channel thro ugh software control, thus making the unfiltered signal available at the output. The input am plifiers are not bypassed. Y ou can use the f ilter bypass to examine the ef fect that the f ilter has on the input[...]

  • Page 48

    Chapter 4 Theory of Operation © National Instruments Corporation 4-17 SCXI-1141/114 2/1143 User Manual channel 0 and continues. Y ou can program the SCXI-1141/1142/114 3 module to start scans with any channel. Parallel Mode When the OUTPUT signal is configured as the rear connector output of channel 0, the rear signal connector simultaneously carr[...]

  • Page 49

    © National Instruments Corporation 5-1 SCXI -1141/1142/ 1143 User Manual 5 Using the SCXI-1141/1142/1143 Module This chapter makes suggestions for developing you r application and provides basic info rmation regarding cal ibration. Developing Y our Application in NI-DAQmx Note If you are not using an NI ADE, using an NI ADE prior to version 8.3, o[...]

  • Page 50

    Chapter 5 Using the SCXI-11 41/1142/1143 Modul e SCXI-1141/1142/1 143 User Manual 5-2 ni.com Figure 5-1. T ypical Program Flowchart for Voltage Measurement Channels Ye s Create Channel Adjust Timing Settings Create a T ask Programmatically Create T ask in D A Q Assistant or MAX No Hardware Timing/T rigger ing? Create T ask Using D A Q Assistant? No[...]

  • Page 51

    Chapter 5 Using the SCXI-1 141/1142/11 43 Module © National Instruments Corporation 5-3 SCXI -1141/1142/ 1143 User Manual General Discussion of T ypical Flowchart The following sections b riefly discuss some considerations for a few of the steps in Figure 5-1. These sections are meant to give an overview o f some of the options and featur es avail[...]

  • Page 52

    Chapter 5 Using the SCXI-11 41/1142/1143 Modul e SCXI-1141/1142/1 143 User Manual 5-4 ni.com When programmat ically adjusting tim ing settings, you can set the t ask to acquire continuously , acqui re a buf fer of samples, or acquire one point at a time. For continuous acquisition, you must use a while loop around the acquisition componen ts e ven [...]

  • Page 53

    Chapter 5 Using the SCXI-1 141/1142/11 43 Module © National Instruments Corporation 5-5 SCXI -1141/1142/ 1143 User Manual Analog Input»General Properties»Advanced»Gain and Offset»Gain Value AI.Gain Specifies a g ain factor to apply to the signal conditioning portion of the channel. The SCXI-1141/1142/1143 sup ports 1, 2, 5, 10, 20, 50, or 100.[...]

  • Page 54

    Chapter 5 Using the SCXI-11 41/1142/1143 Modul e SCXI-1141/1142/1 143 User Manual 5-6 ni.com Table 5-3. NI-DAQmx RTD Measurement P roperties Property Short Nam e Description Analog Input»Temperature» RTD»Type AI.R TD.T ype Specifies the type of R TD connected to the channel. Analog Input»Temperature» RTD»R0 AI.R TD.R0 Specifies the resistance[...]

  • Page 55

    Chapter 5 Using the SCXI-1 141/1142/11 43 Module © National Instruments Corporation 5-7 SCXI -1141/1142/ 1143 User Manual Note This is not a complete list of NI-DA Qmx properties and does not include ev ery property you may need to configure your application. It is a representativ e sample of important properti es to configure for volt age measure[...]

  • Page 56

    Chapter 5 Using the SCXI-11 41/1142/1143 Modul e SCXI-1141/1142/1 143 User Manual 5-8 ni.com Table 5-6. Pro gramming a T ask in LabVIEW Flowchart Step VI or Program Step Create T ask in D A Q Assistant Create a DAQmx Task Name Control located on the Controls »All C ontrol s»I/O» DAQmx Name Co ntrol s subpalette, right-click it, and select New Ta[...]

  • Page 57

    Chapter 5 Using the SCXI-1 141/1142/11 43 Module © National Instruments Corporation 5-9 SCXI -1141/1142/ 1143 User Manual Using a NI-DAQmx Channel Property Node in LabVIEW You can use property no des in LabVIEW to ma nually configure the channels. To create a LabVIEW prope rty node, complete the following steps: 1. Launch LabVIEW . 2. Create the p[...]

  • Page 58

    Chapter 5 Using the SCXI-11 41/1142/1143 Modul e SCXI-1141/1142/1 143 User Manual 5-10 ni.com 6. Right-click ActiveChans , and select Add Element . Left-click the ne w ActiveChans box. Navigate through the m enus, and select the property you wish to define. 7. Change the property to read or write to eith er get the property or write a new value. Ri[...]

  • Page 59

    Chapter 5 Using the SCXI-1 141/1142/11 43 Module © National Instruments Corporation 5-11 SCXI-1141/114 2/1143 User Manual LabWindows/CVI LabWindows/CVI work s with the DAQ Assistant in MAX to generate code for an voltage measurement task . You can then use the appropriate function call to modify the task. To create a configurable channel or task i[...]

  • Page 60

    Chapter 5 Using the SCXI-11 41/1142/1143 Modul e SCXI-1141/1142/1 143 User Manual 5-12 ni.com T o actually create and configure the channel, you would enter something resembling the following example code: Task myTask = new NationalInstruments.DAQmx.Task(“myTa skName”); MyTask.DAQmxCreateAIVoltageChan ( “SC1Mod1/ai0”, // System.String phys [...]

  • Page 61

    Chapter 5 Using the SCXI-1 141/1142/11 43 Module © National Instruments Corporation 5-13 SCXI-1141/114 2/1143 User Manual Calibration The SCXI-1141/1142/1 143 is shipped with a calibration certificate and is calibrated at the factory to the speci fication s described in Appendix A, Specifications . Calibration constants are st ored inside the cali[...]

  • Page 62

    © National Instruments Corporation A-1 SCXI-1141/ 1142/1143 U ser Manual A Specifications This appendix lists the specifications for the SCXI-1141/1142/114 3 module. These specif icati ons are typical at 25 ° C unless otherwise noted. Amplifier Characteristics Number of channels ................ .............. . 8 differential Output signal range[...]

  • Page 63

    Appendix A Specifications SCXI-1141/1142/1 143 User Manual A-2 ni.com DC gain error ........................ .............. ....±0.6% before calibration, ±0.02% after calibration 1 DC input offset ........................ .............. . mV max Filter Characteristics Filter type SCXI-1141 module .............. ............8th-order elliptic SCXI[...]

  • Page 64

    Appendix A Specifications © National Instruments Corporation A-3 SCXI-1141/ 1142/1143 U ser Manual Bandwidth and response time System Noise THD 1 kHz ............... ........... ............ ......... –70 dB 0–25 kHz .............. ........... .............. . –60 dB Input noise ........... ............ ........... ............ Output noise [...]

  • Page 65

    Appendix A Specifications SCXI-1141/1142/1 143 User Manual A-4 ni.com Stability DC gain temperature coef ficient.............20 ppm/ ° C Input offset drift .................. .............. ...... µV/ ° C typ µV/ ° C max AC gain temperature coef ficient.............280 ppm/ ° C Digital Input/Output EXT CLK pin input voltage with respect to DI[...]

  • Page 66

    Appendix A Specifications © National Instruments Corporation A-5 SCXI-1141/ 1142/1143 U ser Manual Physical Figure A-1. SCXI-1141/1142/1143 Dimensions Weight SCXI-1141 and SCXI-114 3 ............ 623 g (22.0 oz) SCXI-1142 ....................... .............. . 676 g (22.8 oz) I/O connectors Rear connector ......................... ....... 50-pin[...]

  • Page 67

    Appendix A Specifications SCXI-1141/1142/1 143 User Manual A-6 ni.com Environmental Operating temperature ............. ........... ....0 to 50 ° C Storage temperature ................. .............. .–20 to 70 ° C Humidity .............. ............... ........... .........10 to 90% RH, noncondensing Maximum altitude ............... ........[...]

  • Page 68

    Appendix A Specifications © National Instruments Corporation A-7 SCXI-1141/ 1142/1143 U ser Manual CE Compliance This product meets the essential re quirements of applicable European Directi ves, as amended for CE marking, as follo w s: • 73/23/EEC; Lo w-V oltage Directi v e (safety) • 89/336/EEC; Electromagnetic Compatibility Directiv e (EMC)[...]

  • Page 69

    © National Instruments Corporation B-1 SCXI-1141/ 1142/1143 U ser Manual B Removing the SCXI-1141/1142/1143 Module This appendix describes how to remov e the SCXI-1141/1142/1143 mod ule from an SCXI chas sis and from MAX. Removing the SCXI-1141/1142/1143 Module from MAX T o remov e a module fr om MAX, complete the follo wing steps after launching [...]

  • Page 70

    Appendix B Removing the SCXI -1141/1142/1143 Module SCXI-1141/1142/1 143 User Manual B-2 ni.com 2. If the SCXI-1141/1142/1143 is the mod ule cabled to the E/M Series D A Q device, disconnect the cable. 3. Remov e an y terminal block that connects to the SCXI-1141/1142/ 1143. 4. Rotate the thumbscrews that secure the SCXI-1141/1142/1143 to the chass[...]

  • Page 71

    © National Instruments Corporation C-1 SCXI-1141/ 1142/1143 U ser Manual C Common Questions This appendix lists common questions rel ated to the use of the SCXI-1141/1142/ 1143. Which version of NI-D AQ w orks with the SCXI-1141/1142/1143, and how do I get th e most curr ent version of NI-D A Qmx? NI recommends that you hav e NI-D A Qmx 8.3 or lat[...]

  • Page 72

    Appendix C Comm on Questions SCXI-1141/1142/1 143 User Manual C-2 ni.com Can I conf igure the SCXI-1141/1142/1143 for use in parallel mode? Y ou can configure the SCXI-1141/1142/1143 for parallel mode using either NI-DA Qmx or T raditional NI-DA Q (Legac y). For more information, refer to Chapter 4, Theory of Operation . How can I get the most accu[...]

  • Page 73

    Appendix C Common Questions © National Instruments Corporation C-3 SCXI-1141/ 1142/1143 U ser Manual In LabVIEW , can I use differen t inpu t limits f or the same SCXI-1141/1142/1 143 channel if I re peat the channel in the SCXI channel string array? No. The SCXI-1141/1142/1143 cann ot dynamically change the gain settings during scanning. Therefor[...]

  • Page 74

    Appendix C Comm on Questions SCXI-1141/1142/1 143 User Manual C-4 ni.com Which accessories can I use to conn ect signals to the front of the SCXI-1141/1142/1 143 module? For information reg arding av ailabl e accessories, refer to Chapter 1, About the SCXI-1141/1142/1143 . How do I control the gain using LabVIEW? The gain of each SCXI-1141/1142/1 1[...]

  • Page 75

    © National Instruments Corporation G-1 SCXI-1141/ 1142/1143 U ser Manual Glossar y Symbol Pref ix V alu e pp i c o 1 0 –1 2 nn a n o 1 0 –9 μ micro 10 –6 m milli 10 –3 k kilo 10 3 Mm e g a 1 0 6 Gg i g a 1 0 9 Tt e r a 1 0 12 Symbols ° degrees > greater than ≥ greater than or equal to < less than ≤ less than or equal to – neg[...]

  • Page 76

    Glossary SCXI-1141/1142/1 143 User Manual G-2 ni.com A A amperes A GND analog ground signal A OUT analog output signal A C alternating current ADE application dev elopment en vironment aliasing the consequence of sampling that causes signals with frequencies higher than half the sampling frequency to appear as lower frequency components B bias curr[...]

  • Page 77

    Glossary © National Instruments Corporation G-3 SCXI-1141/ 1142/1143 U ser Manual DIG GND digital ground signal DIN Deutsche Industrie Norme (German Industrial Standard) DMM digital multimeter E EEPR OM electrically erasable programmable read-o nly memory EXT CLK e xternal clock signal F f c cutof f frequency F ext external frequency G Gg a i n ga[...]

  • Page 78

    Glossary SCXI-1141/1142/1 143 User Manual G-4 ni.com L lowpass filter a filter that passes signals belo w a cutoff frequenc y while blocking signals abov e that frequency M max maximum MB megab ytes min minutes, or minimum MISO Master-In-Slave-Out signal MOSI Master-Out-Slave-In signal multiplex to route one of many input signals to a single output[...]

  • Page 79

    Glossary © National Instruments Corporation G-5 SCXI-1141/ 1142/1143 U ser Manual R rms root mean sq uare rolloff the ratio that a system attenuates signals in the stopban d with respect to the passband, usually defined in decibels per octav e RSVD reserved signal/bit S s seconds S/s samples per second—used to e xpr ess the rate at which a D A Q[...]

  • Page 80

    Glossary SCXI-1141/1142/1 143 User Manual G-6 ni.com T THD total harmonic distortion TTL transistor-transistor logic V Vv o l t s VI virtual instrume nt (a LabV IEW progr am) V rms vo lts, root mean square W working voltage the highest voltage that should be applied to a product during normal use, normally well under the breakdown v oltage for safe[...]

  • Page 81

    © National Instruments Corporation I-1 SCXI -1141/1142/ 1143 User Manual Index A A GND signal front connector (table), 2-3 rear connector (table), 2-9 A OUT signal (table), 2-9 A C-coupled signal connections floating (figure), 2-6 ground-offset (f igure), 2-6 ground-referenced (figure), 2-5 adjusting tim ing and triggeri ng, 5-3 AI+<0..7+> s[...]

  • Page 82

    Index SCXI-1141/1142/1 143 User Manual I-2 ni.com settings in MAX NI-D A Qmx, 3-3 creating a global channel or task, 3-3 troubleshooting self-test verification, 1-5 verifying signal, 3-4 NI-D A Qmx, 3-4 configuration register, 4-3 configuration settings, gain/input range, 3-1 configuring channel properties, 5-4 connectors front signal connector pin[...]

  • Page 83

    Index © National Instruments Corporation I-3 SCXI -1141/1142/ 1143 User Manual signal desc riptions (tab le), 2-3 front signal connector pin assignments (figure), 2-2 functional overvie w of SCXI-1141. See theo ry of operation G gain and offset correction, 4-4 See also calibratio n gain register, 4- 3 gain/input range, configuration, 3-1 ground-of[...]

  • Page 84

    Index SCXI-1141/1142/1 143 User Manual I-4 ni.com Measurement Studio, 1-2 creating code for using SCXI-11141/1142/11 43, 5-11 Module ID register, 4-3 modules, installing, 1-4 multiple x ed mode, an alog out put, 4-16 N National Instruments documentat ion, 1-3 NI-D A Q, 1-2 dri ver software, 1-4 installation, 1-4 NI-D A Qmx configurable settings, 3-[...]

  • Page 85

    Index © National Instruments Corporation I-5 SCXI -1141/1142/ 1143 User Manual removing modules from M AX, B-1 SCXI-1141/1142/ 1143 from SCXI chassis, B-1 requirements for getting started, 1- 2 ripple, real filters, 4-6 RT D measurement properties (table), 5-6 S safety specifications, A-6 SCAN CLK signal digital I/O connections, 2-12 SCXI chassis [...]

  • Page 86

    Index SCXI-1141/1142/1 143 User Manual I-6 ni.com specifications amplifier characteristics, A-1 CD compliance, A-7 digital I/O, A-4 electromagnetic comp atibility, A-6 en vironmental characteristics, A-6 filter characteris tics, A-2 physical, A-5 safety, A-6 stability, A-4 system noise, A-3 W aste Electrical and Electronic Equipment (WEEE), A-7 spe[...]