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TM
SCXI
SCXI-1141/1142/1143 User Manual
SCXI-1141/1142/1143 User Manual
May 2007
371748E-01
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Support Worldwide Technical Support and Product Information ni.com National Instruments Corporate Headquarters 11500 North Mopac Expressway Austin, 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, Czech Republic 420 224 235 774, Denmark 45 45 76 26 00, Finland 385 (0) 9 725 72511, France 33 (0) 1 48 14 24 24, Germany 49 89 7413130, India 91 80
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Important Information Warranty The SCXI-1141, SCXI-1142, and SCXI-1143 modules are warranted against defects in materials and workmanship for a period of one year from the date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace equipment that proves to be defective during the warranty period. This warranty includes parts and labor. The media on which you receive National Instruments software are warranted not to fail to
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Conventions The following conventions are used in this manual: <> Angle brackets that contain numbers separated by an ellipsis represent a range of values associated with a bit or signal name—for example, AO <3..0>. » The » symbol leads you through nested menu items and dialog box options to a final action. The sequence File»Page Setup»Options directs you to pull down the File menu, select the Page Setup item, and select Options from the last dialog box. This icon denotes a note, which aler
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Contents Chapter 1 About the SCXI-1141/1142/1143 What You Need to Get Started ......................................................................................1-2 National Instruments Documentation ............................................................................1-3 Installing Application Software, NI-DAQmx, and the DAQ Device ............................1-4 Installing the SCXI-1141/1142/1143 into an SCXI Chassis or a PXI/SCXI Combination Chassis.................................
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Contents Chapter 4 Theory of Operation Power-Up State.............................................................................................................. 4-1 Digital Control Circuitry ............................................................................................... 4-3 Input Amplifiers ............................................................................................................ 4-3 Correcting Gain and Offset Errors ..........................................
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Contents Appendix B Removing the SCXI-1141/1142/1143 Module Appendix C Common Questions Glossary Index Figures Figure 2-1. Ground-Referenced Signal Connection.................................................2-4 Figure 2-2. Floating Signal Connection ...................................................................2-5 Figure 2-3. Ground-Referenced AC-Coupled Signal Connection ...........................2-5 Figure 2-4. Ground Offset AC-Coupled Signal Connection...................................
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Contents 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................................................................ 2-8 Table 2-3. SCXI-1141/1142/1143 Rear Communication Signals.......................... 2-9 Table 2-4. SCXIbus to SCXI-1141/1142/1143 Module Rear Signal Connector to DAQ Device Pin E
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1 About the SCXI-1141/1142/1143 This chapter describes the SCXI-1141/1142/1143 module, and explains how to install and remove the hardware and software. The SCXI-1141/1142/1143 module has eight lowpass filters and eight differential-input amplifiers. The SCXI-1141 has elliptic filters; the SCXI-1142, Bessel filters; and the SCXI-1143, Butterworth filters. You can use the SCXI-1141/1142/1143 module for lowpass filtering and antialiasing applications as well as for general-purpose signal ampli
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Chapter 1 About the SCXI-1141/1142/1143 What You Need to Get Started To set up and use the SCXI-1141/1142/1143 module, you need the following: ❑ Hardware – SCXI-1141/1142/1143 module – One of the following terminal blocks: � SCXI-1304 � SCXI-1305 – An SCXI chassis or PXI/SCXI combination chassis – One of the following: � E/M Series DAQ device � SCXI-1600 – A computer if using an SCXI chassis – Cabling, cable adapter, and sensors as required for your application ❑ Software –NI-DAQ – One of the
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Chapter 1 About the SCXI-1141/1142/1143 DAQ. Select the appropriate information for your 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 acquisition (DAQ) systems. You could have any of several types of manuals depending on the hardware and software in the system. Use the manuals you have as follows: � SCXI chassis or PXI/SCXI combination chassis manual—Read this
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Chapter 1 About the SCXI-1141/1142/1143 � The following 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 install your application software, NI-DAQmx driver software, and the E/M Series DAQ device to which you will connect the SCXI-1141/1142/1143. NI-DAQ 8.3 or later is recommended to configure and program
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Chapter 1 About the SCXI-1141/1142/1143 Verifying the SCXI-1141/1142/1143 Installation in Software Refer to the SCXI Quick Start Guide for information on verifying the SCXI installation. Installing SCXI Chassis and Modules in Software Refer to the SCXI Quick Start Guide for information on installing chassis and modules using NI-DAQmx in software. Troubleshooting the Self-Test Verification If the self-test verification did not verify the chassis configuration, complete the steps in this secti
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Chapter 1 About the SCXI-1141/1142/1143 � 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 module: SCXI-XXXX or 1141/1142/1143, hardware in chassis is: SCXI-YYYY, 1141/1142/1143, or Empty, complete the following troubleshooting steps to correct the error. 1. Expand NI-DAQmx Devices. 2. Right-click the SCXI chassis and click Properties to load the chassis configurator. 3. Under the Modules tab
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2 Connecting Signals This chapter describes input and output signal connections to the SCXI-1141/1142/1143 module through the front and rear signal connectors. Caution Connections that exceed any of the maximum ratings of input or output signals on the SCXI-1141/1142/1143 module can damage the SCXI-1141/1142/1143 module, the SCXIbus, any connected DAQ device, and the computer with which the DAQ device is used. NI is not liable for any damage resulting from such signal connections. Front Con
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Chapter 2 Connecting Signals Table 2-1. Front Signal Pin Assignments Front Connector Diagram Pin Number Column A Column B Column C 32 AI 0 + NC AI 0 – Column 31 NC NC NC A B C 30 AI 1 + NC AI 1 – 32 29 NC NC NC 31 28 A GND NC A GND 30 27 NC NC NC 29 28 26 AI 2 + NC AI 2 – 27 25 NC NC NC 26 24 AI 3 + NC AI 3 – 25 23 NC NC NC 24 22 A GND NC A GND 23 22 21 NC NC NC 21 20 AI 4 + NC AI 4 – 20 19 NC NC NC 19 18 AI 5 + NC AI 5 – 18 17 17 NC NC NC 16 16 A GND NC A GND 15 15 NC NC NC 14 14 AI
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Chapter 2 Connecting Signals Front Connector Signal Descriptions Pins Signal Names Description A32, A30, A26, A24, AI+<0..7+> Positive input channels—these pins connect to the A20, A18, A14, A12 noninverting inputs of the instrumentation amplifier of each channel. C32, C30, C26, C24, AI–<0..7–> Negative input channels—these pins connect to the C20, C18, C14, C12 inverting inputs of the instrumentation amplifier of each channel. A28, A22, A16, C28, A GND Analog ground—these pins connect to th
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Chapter 2 Connecting Signals analog ground. The inputs are protected against maximum input voltages of up to ±15 V powered off and ±30 V powered on. Caution Exceeding the differential or common-mode input voltage limits distorts input signals. Exceeding the maximum common-mode input voltage rating can damage the SCXI-1141/1142/1143 module, the SCXIbus, and the DAQ device. NI is not liable for any damage resulting from such signal connections. All eight channels have fully differential inputs
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Chapter 2 Connecting Signals Figure 2-2 illustrates how to connect a non-referenced (floating) signal source to an SCXI channel. IN+ IN– 100 kΩ SCXI-1141/1142/1143 A GND A Figure 2-2. Floating Signal Connection For AC-coupled signals, connect an external resistor from the AC-coupled input channel to ground. This provides a DC path for the amplifier input bias current. Typical resistor values range from 100 kΩ to 10 MΩ. This solution, although necessary, lowers the input impedance of the cha
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Chapter 2 Connecting Signals 1 µF IN+ 1 MΩ 1 µF IN– 1 MΩ SCXI-1141/1142/1143 A GND A Figure 2-4. Ground Offset AC-Coupled Signal Connection 1 µF IN+ 1 MΩ IN– 100 kΩ SCXI-1141/1142/1143 A GND A 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-1141/1142/1143 module to control filter cutoff frequency for special purposes. The clock should be a TTL-logic-level or CMOS-logic-level square wave, with a f
