Manuale d’uso / di manutenzione del prodotto SCXI -1122 del fabbricante National Instruments
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© Copyright 1993, 1999 National Instruments Corporation. All Rights Reserved. User Manual Sixteen-Channel Isolated Transducer Multiplexer Module for Signal Conditioning September 1999 Edition Part Nu.
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Warranty T h e SCX I - 1 1 2 2 is war r a n t e d ag a inst d e f ect s i n m ate ri a l s a n d w or k m a nshi p f o r a p e ri o d o f o n e yea r f r o m t h e d ate o f shipm e nt, as evidenced by receipt s or other document a tion.
WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS (1) NATIONAL INSTRUMENTS PRODUC TS ARE NOT DESIGNED WITH COMPONENTS AND TESTING FOR A LEVEL OF R ELIABILITY SUI TABLE FOR USE IN O R IN CONNECTIO.
© National Instruments Corporation v SCXI-1122 User Manual Contents About This Manual ............................................................................................................. ix Organization of This Manual .......................
Contents SCXI-1122 User Manual vi © National Instruments Corporation Chapter 5 Calibration ............................................................................................................................. 5-1 Overview ....................
Contents © National Instruments Corporation vii SCXI-1122 User Manual Figures Figur e 1-1. The Relationship between the Programming Environment, NI-DAQ, and Your Hardwar e ..............................................................................
© National Instruments Corporation ix SCXI-1122 User Manual About This Manual This manual describes the electrical and mechanical aspects of the SCXI -1122 and contains information concerning its operation.
About This Manual SCXI-1122 User Manual x © National Instruments Corporation Conventions Used in This Manual The following conventions are used in this manual. bold italic Bold italic text denotes a note, caution, or warning. italic Italic text denotes emphasis, a cross reference, or an introduction to a key concept.
About This Manual © National Instruments Corporation xi SCXI-1122 User Manual The National Instruments Documentation Set The SCXI-1122 User Manual is one piece of the documentation set for your SCXI system.
About This Manual SCXI-1122 User Manual xii © National Instruments Corporation Customer Communication National Instruments wants to receive your comments on our products and manuals. We are interested in the applications you develop with our products, and we want to help if you have problems with them.
© National Instruments Corporation 1-1 SCXI-1122 User Manual Chapter 1 Introduction This chapter describes the SCXI-1122; lists the contents of your SCXI-1122 kit; describes the optional software, optional equipment, and custom cables; and explains how to unpack the SCXI-1122.
Introduction Chapter 1 SCXI-1122 User Manual 1 - 2 © National Instruments Corporation Software Programming Choices There are four options to choose from when programming your National Instruments plug-in DAQ board and SCXI hardware. You can use LabVIEW, LabWindows, NI-DAQ, or register- level programming software.
Chapter 1 Introduction © National Instruments Corporation 1-3 SCXI-1122 User Manual NI-DAQ also internally addresses many of the complex issues between the computer and the plug-in board such as programming interrupts and DMA controllers.
Introduction Chapter 1 SCXI-1122 User Manual 1 - 4 © National Instruments Corporation Register-Level Programming The final option for programming any National Instruments DAQ hardware is to write register- level software. Writing register-level programming software can be very time consuming and inefficient, and is not recommended for most users.
Chapter 1 Introduction © National Instruments Corporation 1-5 SCXI-1122 User Manual Custom Cables The SCXI-1122 rear signal connector is a 50-pin male ribbon-cable header. The manufacturer part number that National Instruments uses for this header is as follows: • AMP Inc.
© National Instruments Corporation 2-1 SCXI-1122 User Manual Chapter 2 Configuration and Installation This chapter describes how to configure the SCXI-1122 jumpers and how to install the SCXI-1122 into the SCXI chassis. Module Configuration The SCXI-1122 contains two jumpers that are shown in the parts locator diagram in Figure 2-1.
Configuration and Installation Chapter 2 SCXI-1122 User Manual 2-2 © National Instruments Corporation Figure 2-1. SCXI-1122 Parts Locator Diagram.
Chapter 2 Configuration and Installation © National Instruments Corporation 2-3 SCXI-1122 User Manual Digital Signal Connections Note: If nothing is cabled to the SCXI-1122 rear signal connector, the position of jumper W2 is irrelevant.
Configuration and Installation Chapter 2 SCXI-1122 User Manual 2-4 © National Instruments Corporation Table 2-2. Jumper W1 Settings Jumper Description Configuration Grounding, shielding, and referenc.
Chapter 2 Configuration and Installation © National Instruments Corporation 2- 5 SCXI-1122 User Manual Table 2-3. User-Defined Current Receiver Resistors (Continued) Input Channel Resistor Reference .
Configuration and Installation Chapter 2 SCXI-1122 User Manual 2-6 © National Instruments Corporation Hardware Installation You can install the SCXI-1122 in any available SCXI chassis slot.
© National Instruments Corporation 3- 1 SCXI-1122 User Manual Chapter 3 Signal Connections This chapter describes the input and output signal connections to the SCXI -1122 module via the SCXI-1122 front connector and rear signal connector.
Signal Connections Chapter 3 SCXI-1122 User Manual 3- 2 © National Instruments Corporation Connections, including power signals to ground and vice versa, that exceed any of the maximum signal ratings on the SCXI-1122 can damage any or all of the boards connected to the SCXI chassis, the host computer, and the SCXI-1122 module.
Chapter 3 Signal Connections © National Instruments Corporation 3- 3 SCXI-1122 User Manual Front Connector Figure 3-1 shows the pin assignments for the SCXI-1122 front connector. ! I f a relay fails there exists a potential shock hazard on the inputs that are not in contact with hazardous voltages.
Signal Connections Chapter 3 SCXI-1122 User Manual 3-4 © National Instruments Corporation Front Signal Connection Descriptions Pin Signal Name Description A1 TEMP- Temperature Sensor Reference–This pin is tied to the temperature sensor reference in the terminal block and to the isolation amplifier negative input in the module.
Chapter 3 Signal Connections © National Instruments Corporation 3- 5 SCXI-1122 User Manual The signals on the front connector are all analog except pins A7, and A31, which are digital. The analog signals are grouped into analog input channels, excitation channels, and temperature sensor signals.
Signal Connections Chapter 3 SCXI-1122 User Manual 3-6 © National Instruments Corporation Vs Vcm + - Figure 3-2. Ground-Referenced Signal Connection with High Common-Mode Voltage Vs + - Figure 3-3. Floating Signal Connection Referenced to Chassis Ground for Better SNR Vs R b C c + - Figure 3-4.
Chapter 3 Signal Connections © National Instruments Corporation 3-7 SCXI-1122 User Manual Vs R b C c Vcm + - Figure 3-5. AC-Coupled Signal Connection with High Common-Mode Voltage For AC-coupled signals, connect an external resistor from the positive input channel to the signal reference to provide the DC path for the positive input bias current.
Signal Connections Chapter 3 SCXI-1122 User Manual 3- 8 © National Instruments Corporation Scanned 100 times CH0 (one sample) CH1 (one sample) CH2 (one sample) CH3 (one sample) No 100 Scans Done? Ye .
Chapter 3 Signal Connections © National Instruments Corporation 3-9 SCXI-1122 User Manual Table 3-1. Maximum Load per Excitation Channel Excitation Level Maximum Load 3.333 V 225 mA 1 mA 5 k Ω Using the Internal Half-Bridge Completion Your SCXI-1122 includes half-bridge completion for half-bridge and quarter-bridge setups.
Signal Connections Chapter 3 SCXI-1122 User Manual 3-10 © National Instruments Corporation Rear Signal Connector Note: If you are using the SCXI-1122 with a National Instruments DAQ board and cable assembly, you do not need to read the remainder of this chapter.
Chapter 3 Signal Connections © National Instruments Corporation 3-11 SCXI-1122 User Manual Rear Signal Connection Descriptions Pin Signal Name Description 1, 2 AOGND Analog Output Ground–These pins are connected to the analog reference when jumper W1 is in position AB-R0.
Signal Connections Chapter 3 SCXI-1122 User Manual 3-12 © National Instruments Corporation In particular, when using differential input DAQ boards such as the MIO-16 boards, it is preferable to leave jumper W1 in its factory setting or in position AB-R1 to avoid ground loops.
Chapter 3 Signal Connections © National Instruments Corporation 3-13 SCXI-1122 User Manual Table 3-2. SCXIbus to SCXI-1122 Rear Signal Connector to DAQ Board Pin Equivalences SCXIbus Line SCXI-1122 R.
© National Instruments Corporation 4-1 SCXI-1122 User Manual Chapter 4 Theory of Operation This chapter contains a functional overview of the SCXI-1122 module and explains the operation of each functional unit making up the SCXI-1122. Functional Overview The block diagram in Figure 4-1 illustrates the key functional components of the SCXI -1122.
Theory of Operation Chapter 4 SCXI-1122 User Manual 4-2 © National Instruments Corporation IEX+ IEX- VEX+ VEX/2 VEX- Current Source V oltage Source Configuration Register LPF-Sel Amplifier Input Sele.
Chapter 4 Theory of Operation © National Instruments Corporation 4-3 SCXI-1122 User Manual The major components of the SCXI-1122 are as follows: • The rear signal connector • The SCXIbus connecto.
Theory of Operation Chapter 4 SCXI-1122 User Manual 4-4 © National Instruments Corporation banks which switch synchronously. The eight upper channels (0 through 7) operate as voltage sense channels and one out of eight is connected to the amplifier at any given point in time.
Chapter 4 Theory of Operation © National Instruments Corporation 4- 5 SCXI-1122 User Manual Excitation Output Channels In addition to the isolated input channels, the SCXI-1122 has isolated excitation channels, one 3.333 V voltage output source and one 1 mA current output source.
Theory of Operation Chapter 4 SCXI-1122 User Manual 4-6 © National Instruments Corporation gauge resistor–to complete the bridge network. Connect this resistor in your SCXI-1322 terminal block between the CH+ and VEX- terminals.
Chapter 4 Theory of Operation © National Instruments Corporation 4-7 SCXI-1122 User Manual Note: Always connect the current excitation terminals outside the sense terminals as shown in both Figures 4-2 and 4-3. Each approach has its advantages and disadvantages as listed in Table 4-2.
© National Instruments Corporation 5-1 SCXI-1122 User Manual Chapter 5 Calibration This chapter discusses the calibration procedures for the SCXI-1122. Overview The onboard calibration hardware that calibrates the SCXI-1122, consists of an EEPROM to store the calibration constants and an auto-zero channel on the amplifier input selector.
Calibration Chapter 5 SCXI-1122 User Manual 5-2 © National Instruments Corporation - Resolution 8 1 / 2 digits • For the excitation channels, you need a voltmeter with the following specifications: - Accuracy ± 0.
Chapter 5 Calibration © National Instruments Corporation 5-3 SCXI-1122 User Manual • To select positive and negative full scale to be the two calibration points, apply -9.9 V/G s and 9.9 V/G s. . a. Apply -9.9 V/G s to the amplifier input. b. Measure the input voltage with the DMM and store the measured value.
Calibration Chapter 5 SCXI-1122 User Manual 5-4 © National Instruments Corporation Excitation Calibration When using the excitation channels, you must retrieve the correction factors for the current and voltage from the EEPROM before using them in your transducer conversion formulas.
© National Instruments Corporation A- 1 SCXI-1122 User Manual Appendix A Specifications This appendix lists the specifications for the SCXI-1122. These are typical at 2 5 ° C unless otherwise stated.
Specifications Appendix A SCXI-1122 User Manual A-2 © National Instruments Corporation Transfer Characteristics Nonlinearity 0.01% FSR Offset error Gain ≥ 1 ± (6 µ V + 1,240 µ V/gain) Gain < 1 ± (352 µ V + 1,240 µ V/gain) Gain error Gain ≥ 1 ± 0.
° Appendix A Specifications © National Instruments Corporation A- 3 SCXI-1122 User Manual Excitation Output Characteristics Channels 2 (1 voltage and 1 current) Bridge type Quarter, half, or full Bridge completion Two 2.5 k Ω ± 0.02% ratio tolerance resistors Voltage Mode Level 3.
© National Instruments Corporation B- 1 SCXI-112 2 User Manual Appendix B Customer Communication For your convenience, this appendix contains forms to help you gather the information necessary to help us solve technical problems you might have as well as a form you can use to comment on the product documentation.
Technical Support Form ___________________________________________________ Photocopy this form and update it each time you make changes to your software or hardware, and use the completed copy of this form as a reference for your current configuration.
SCXI-1122 Hardware Configuration Form Record the settings and revisions of your hardware and software on the line to the right of each item. Complete a new copy of this form each time you revise your software or hardware configuration, and use this form as a reference for your current configuration.
Register-Level Programmer Manual Request Form National Instruments encourages you to comment on the documentation supplied with our products. This information helps us provide quality products to meet your needs.
Documentation Comment Form National Instruments encourages you to comment on the documentation supplied with our products. This information helps us provide quality products to meet your needs.
© National Instruments Corporation Glossary-1 SCXI-1122 User Manual Glossary Prefix Meaning Value p- pico- 10 -12 n- nano- 10 -9 µ - micro- 10 -6 m- milli- 10 -3 k- kilo- 10 3 M- mega- 10 6 Numbers/.
Glossary SCXI-1122 User Manual Glossary-2 © National Instruments Corporation CH#+ Positive Input Channel Number signal CH#- Negative Input Channel Number signal CJC cold-junction compensation CJR col.
Glossary © National Instruments Corporation Glossary-3 SCXI-1122 User Manual INTR* Interrupt signal I/O input/output M m meters MB megabytes of memory MCH#+ Positive Analog Output Channel Number sign.
Glossary SCXI-1122 User Manual Glossary-4 © National Instruments Corporation s seconds SENSE- Negative Voltage Sense signal SENSE+ Positive Voltage Sense signal SERCLK Serial Clock signal SERDATIN Se.
© National Instruments Corporation Index- 1 SCXI-1122 User Manual Index Numbers +5 V signal, 3-4 A AC-coupled signal connection with high common-mode voltage (illustration), 3-7 Address Handler Regis.
Index SCXI-1122 User Manual Index- 2 © National Instruments Corporation E EEPROM, 5-1 environment specifications, A-3 equipment, optional, 1-4 to 1-5 excitation channel signal connections, 3-8 to 3-9.
Index © National Instruments Corporation Index- 3 SCXI-1122 User Manual M manual . See documentation. MCH0 ± signal, 3-11, 3-12 MIO-16 boards SCXIbus to SCXI-1122 rear signal connector to DAQ board pin equivalences (table), 3-13 MISO line, 2-3 module configuration .
Index SCXI-1122 User Manual Index- 4 © National Instruments Corporation ground for better SNR (illustration), 3-6 floating signal connection referenced to chassis ground for better SNR (illustration).
Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il National Instruments SCXI -1122 è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del National Instruments SCXI -1122 - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso National Instruments SCXI -1122 imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul National Instruments SCXI -1122 ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il National Instruments SCXI -1122, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del National Instruments SCXI -1122.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il National Instruments SCXI -1122. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo National Instruments SCXI -1122 insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
