Manuale d’uso / di manutenzione del prodotto NI 7831R del fabbricante National Instruments
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Reconfigurable I/O NI 7831R User Manual Reconfigurable I/O Devices for PCI/PXI/CompactPCI Bus Computers NI 7831R User Manual April 2004 Edition Part Number 3704 89B-01.
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 O.
Important Information Warranty The NI 7831R is warranted agains t defects in materials and workmanship for a p eriod of one year from the date of s hipment, as ev idenced by receipts or other documentation. National Ins truments will, at its option, repair or replace equi pment that proves to be defect ive during the warranty period.
Compliance Compliance with FCC/Canada Radio Frequency Interference Regulations Determining FCC Class The Federal Communications Commission (FCC) has rules to protect wireless co mmunications from inte rference. The FCC places digital electronics into two classes.
© National Instruments Corporation v NI 7831R User Manual Contents About This Manual Conventions ............ .............. ........... .............. ............ .............. .............. ........... ............. v ii Reconfigurable I/O Documentation .
Contents NI 7831R Use r Manual vi ni.com Single-Ended Connection Considerations ...... ........... .............. .............. ......... 2-12 Single-Ended Connections for Fl oating Signal Sources (RSE Input Mode) .............. ............ ........
© National Instruments Corporation vii NI 7831R User Manual About This Manual This manual describes the electrical and mechanical aspects of the National Instruments 7831R device and contains information concerning its operation and programming. The NI 7831R device is a Reconfigurable I/O (RIO) device.
About This Manual NI 7831R Use r Manual viii ni.com programs, subprograms, su broutines, d e vice names, functions, operation s, variables, f ilename s, and extensions. Reconfigurable I/O Documentation The NI 7 831R User Manual is one piece of the documentation set for your RIO system and application.
About This Manual © National Instruments Corporation ix NI 7831R User Manual Related Documentation The following documents contain information you migh t find helpful: • NI Dev eloper Zone tu torial, Field Wiring and Noise Considerati ons for Analog Signals , at ni.
© National Instruments Corporation 1-1 NI 7831R User Manual 1 Introduction This chapter describes the NI 7831R, de scribes the concept of the Reconfigurable I/O device, describes the opti onal software and equipment, and contains information about the NI 7831 R.
Chapter 1 Introduction NI 7831R Use r Manual 1 -2 ni.com between devices. The NI PXI-7831R accesses the R TSI bus through the PXI trigger lines implemented on the PXI backplane. Refer to Appendix A, Sp ecifications , for detailed NI 7831R specifications.
Chapter 1 Introduction © National Instruments Corporation 1-3 NI 7831R User Manual Over view of Reconfigurable I/O This section explains reconfigurable I/O and describes how to use the FPGA Module to b uild high-l evel functions i n hardware.
Chapter 1 Introduction NI 7831R Use r Manual 1 -4 ni.com User -Defined I/O Resources You can create your own custom m easurements using the fixed I/O resources. For example, one application migh t require an event counter that increments when a rising edge appears on any of three digital input lines.
Chapter 1 Introduction © National Instruments Corporation 1-5 NI 7831R User Manual The FPGA logic provides timing, triggerin g, processing, and custom I/O measurements. Each fix ed I/O resource used by the application uses a small portion of the FPGA logic that contro ls the fixed I/O resource.
Chapter 1 Introduction NI 7831R Use r Manual 1 -6 ni.com Y ou can use Interactive Front P a nel Commu nicati on to communicate directly with the V I running on th e FPGA. Y ou can use Programmatic FPGA Interface Comm unication to programmatically co ntrol and communicate with FPGA VIs from host VIs.
Chapter 1 Introduction © National Instruments Corporation 1-7 NI 7831R User Manual Cables and Optional Equipment National Instruments offers a v ariety of products you can use with R Series devices, including cables, connector blocks, and other accessories, as shown in Table 1-2.
Chapter 1 Introduction NI 7831R Use r Manual 1 -8 ni.com Refer to Appendix B, Con necting I/O Signals , for more information about using these cables and acce ssories to connect I/O signals to the NI 7831R. Refer to ni.com/catalog for the most current cabling option s.
Chapter 1 Introduction © National Instruments Corporation 1-9 NI 7831R User Manual Safety Information The following section contains important safety info rmation that you must follow when installi ng and using the NI 7831R. Do not operate the NI 7831R in a manner no t specified in this document.
Chapter 1 Introduction NI 7831R Us er Manual 1-10 ni.com Operate the NI 7831R at or below the installation category 1 listed in the section Maximum worki ng voltage , in Appendix A, Specifications .
© National Instruments Corporation 2-1 NI 7831R User Manual 2 Hardware Over view of the NI 7831R This chapter presents an overview of the hardware functions and I/O connectors on the NI 7831R. Figure 2-1 shows a block diagram for the NI 7831R. Figure 2-2 shows the parts locator diagram for th e NI PXI-7831R.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Use r Manual 2 -2 ni.com Figure 2-2. Parts Locator Diagram for the NI PXI-7831R SW1.
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-3 NI 7831R User Manual Figure 2-3. Parts Locator Diagram for the NI PCI-7831R Analog Input The NI 7831R has eight independent, 16-bit AI channels that yo u can sample simultaneously or at di fferent rates.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Use r Manual 2 -4 ni.com Input Modes The NI 7831R input mode is softw are configurable. The input channels support three input modes—differen tial (DIFF), referenced single-ended (RSE), and nonreferenced singl e-ende d (NRSE).
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-5 NI 7831R User Manual Connecting Analog Input Signals The AI signals for the NI 7831R are AI<0..7>+, AI<0..7> –, AIGND, and AISENSE. The AI<0..7>+ and AI<0.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Use r Manual 2 -6 ni.com Figure 2-4. NI 7831R Instrument ation Amplifier The instrumentation amplifier app lies common-mode vo ltage rejection and presents high input impedance to the AI signals connected to the NI 7831R.
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-7 NI 7831R User Manual T ypes of Signal Sources When configuring t he input channels and m aking signal co nnections, you must first det ermine whether the signal sources are fl oating or ground referenced.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Use r Manual 2 -8 ni.com Figure 2-5. Summary of Analog Input Connections + – + – V 1 AI< i > AISENSE AIGND< i > + – + – V 1 AI< i > AISENSE AIGND< i > See text f or information on bias resistors.
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-9 NI 7831R User Manual Differential Connection Consid erations (DIFF Input Mode) In DIFF input mode, the NI 7831R m easures the difference between the positive and negativ e inputs.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Us er Manual 2-10 ni.com Figure 2-6. Differential Input Connections for Ground-Referenced Signals W ith this connecti on type, the instrumentati on.
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-11 NI 7831R User Manual Figure 2-7. Differential Input Connections for Nonreferenced Signals Figure 2-7 shows two bias resistors connected in parallel with the signal leads of a floating signal source.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Us er Manual 2-12 ni.com Y ou can fully balance the signal path by connecting another resistor of the same value between the positi ve input and AIGND, as shown in Figure 2-7.
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-13 NI 7831R User Manual In single-ended input modes, electrostatic and magn etic noise couples into the signal connection s more than in differential input modes. The couplin g is the result of dif ferences in the signal path.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Us er Manual 2-14 ni.com positive and negativ e inputs of the inst rumentation amplifier. The instrumentation ampli fier rejects this di fference.
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-15 NI 7831R User Manual Analog Output The NI 7831R has eight 16-bit AO channels. The bipolar output range is fixed at ± 10 V . Some applicatio ns require that the A O channels power on to known v oltage levels.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Us er Manual 2-16 ni.com Figure 2-10. Analog Output Connections Digital I/O The NI 7831R has 96 bidirectional DIO lines that yo u can individually configure for either input or o utput. When the system po wers on, th e DIO lines are high-impedance.
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-17 NI 7831R User Manual T o interface to 5 V CMOS devices, you mu st provide an external pull-up resistor to 5 V . This resistor pulls up the 3.3 V digital outp ut from the NI 7831R to 5 V CMO S logic levels.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Us er Manual 2-18 ni.com Figure 2-11 shows signal connections for three typical DIO applications. Figure 2-11. Example Digital I/O Connections Figure 2-11 s hows DIO<0.. 3> configured for digit al input and DIO<4.
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-19 NI 7831R User Manual paired with po wer or ground. Because the DIO lines that are twisted with other DIO lines can couple noise onto each other , use these lines for static signals or non-edge-sensitiv e, low-frequenc y digital signals.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Us er Manual 2-20 ni.com the remaining de vices on that PXI b us segment must hav e PXI/TR IG0 configured as an input. Caution Do not driv e th e same R T SI trigger bus line with the NI 783 1R and another device simultaneously .
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-21 NI 7831R User Manual The left local b us lines from the left peripheral slot of a PXI backplane (Slot 2) are routed to th e star trigger lines of up to 13 other peripheral slots in a two-segment PXI system.
Chapter 2 Hardware Overview of the NI 7831R NI 7831R Us er Manual 2-22 ni.com 4. Reinsert the NI 7831R into the PXI/CompactPCI ch assis or PCI computer . Refer to the Installing the Hardware section of the Getting Started with the NI 7831R d ocument for inst allation instruction s.
Chapter 2 Hardware Over view of the NI 7831R © National Instruments Corporation 2-23 NI 7831R User Manual Field Wiring Considerations Environmental noise can se riously affect the meas urement accuracy of the device if you do not take proper care when running signal wires bet ween signal sources and the device.
© National Instruments Corporation 3-1 NI 7831R User Manual 3 Calibration Calibration is the process of determin ing and/or adjusting the accuracy of an instrument to m inimize measurement an d output voltage errors. On the NI 7831R, onboard calibratio n DACs (CalDACs) correct these errors.
Chapter 3 Calibr ation NI 7831R Use r Manual 3 -2 ni.com If you have NI-RIO installed, you can find the internal calibration utility at Start»All Programs»National Instruments»NI-RIO» device »Cali brate 7831R Device . Device is the NI PXI-7831R or NI PCI-7831R device.
© National Instruments Corporation A- 1 NI 7831R User Manual A Specifications This appendix lists the specifications of the NI 7831R. These specifications are typical at 25 °C unless otherwise noted. Analog Input Input Characteristics Number of channels .
Appendix A Specifications NI 7831R Use r Manual A-2 ni.com Overvoltage protection ............ .............. .± 42 V Data transfers ........................ ...... ...... ......Interrupts, programmed I/O Accuracy Information DC T ransfer Characteristi cs INL .
Appendix A Specifications © National Instruments Corporation A- 3 NI 7831R User Manual Settling T ime Crosstalk.............. .............. ..................... –80 dB, DC to 100 k Hz Analog Output Output Characteristics Number of channels ......
Appendix A Specifications NI 7831R Use r Manual A-4 ni.com DC T ransfer Characteristi cs INL ............... .............. ........... .............. ....± 0.5 LSB typ, ± 4.0 LSB max DNL ............. ......................... ..................± 0.
Appendix A Specifications © National Instruments Corporation A- 5 NI 7831R User Manual Digital logic lev els Maximum output current I max (source)..... .............. .............. .... 5.0 mA I max (sink) ......................... .............. . 5.
Appendix A Specifications NI 7831R Use r Manual A-6 ni.com Phase locked to PXI 10 MHz Clock(NI PXI-7831R only ) . ............... ....Adds 350 ps jitter, 300 ps skew Additional frequency depen dent jitter 40 MHz ............ .............. ...........
Appendix A Specifications © National Instruments Corporation A- 7 NI 7831R User Manual by the digital outputs use the following eq uation: Where j is the number of digital outputs being used to source current. Power available at I/O connectors ......
Appendix A Specifications NI 7831R Use r Manual A-8 ni.com chassis, tested in accordance with IEC-60068-2-1 and IEC-60068-2-2 Relative humidity range...................... .... 10 to 9 0%, noncondensing , tested in accordance with IEC-60068-2-56 Altitude .
Appendix A Specifications © National Instruments Corporation A- 9 NI 7831R User Manual Safety This product is designed to meet the requirements of the follow ing standards of safety for electrical e quipment for measurement, control, and laboratory use: • IEC 61010-1, EN 61010-1 • UL 3111-1, UL 61010B-1 • CAN/CSA C22.
© National Instruments Corporation B- 1 NI 7831R User Manual B Connecting I/O Signals This appendix describes how to make input and output signal connections to the NI 7831R I/O connectors. The NI 7831R has two DIO connectors with 40 DIO lines per connector , and one MIO connector with eight AI lines, eight A O lines, and 16 DIO lines.
Appendix B Connecting I/O Signals NI 7831R Use r Manual B-2 ni.com Figure B-2 shows the I/O connector pin assignments for the I/O connectors on the NI 7831R. The DIO connector pin assignment applies to connectors <1..2> on the NI 7831R. The MIO connector pin assignment applies to connector 0 on the NI 7831R.
Appendix B Connecting I/O Signals © National Instruments Corporation B- 3 NI 7831R User Manual . Caution Connections that exceed any of the maximum ratings of input or output si gnals on the NI 7831R can da mage the NI 7831R and the co mputer . Maximum input rating s for each signal are in the Protection colu mn of T able B-2.
Appendix B Connecting I/O Signals NI 7831R Use r Manual B-4 ni.com Connecting to CompactRIO Extension I/O Chassis Y ou can use the CompactRIO R Series Expansion chassis and CompactRIO I/O modules with the NI 7831R.
Appendix B Connecting I/O Signals © National Instruments Corporation B- 5 NI 7831R User Manual Connecting to 5B and SSR Signal Conditioning NI provides cables that allow you to connect signals from the NI 7831R directly to 5B backplanes for analog signal conditio ning and SSR backplanes for digital signal conditioning .
Appendix B Connecting I/O Signals NI 7831R Use r Manual B-6 ni.com Figure B-3. Connector Pinouts when Using NSC68-262650 Cable The NSC68-5050 cable connects th e signals on the NI 7831R DIO connectors directly to SSR backplanes for digital signal cond itioning.
Appendix B Connecting I/O Signals © National Instruments Corporation B- 7 NI 7831R User Manual NSC68-5050 cable header . In this case, you hav e access only to the channels that exist on both the SSR backplane and the N SC68-5050 cable header you are using.
© National Instruments Corporation C- 1 NI 7831R User Manual C Using the SCB-68 Shielded Connector Block This appendix describes how to connect input and output signals to the NI 7831R with the SCB-68 shielded connector block. The SCB-68 has 68 screw terminals for I/O signal connections.
© National Instruments Corporation D-1 NI 7831R User Manual D T echnical Support and Professional Ser vices Visit the following sections of the National Instruments Web site at ni.com for technical support an d professional services: • Support —Online technical support resources at ni.
Appendix D T e chnical Support and Professional Ser vices NI 7831R Use r Manual D-2 ni.com If you searched ni.com and could not find the answers you need, contact your local off ice or NI corporat e h eadquarters. Phone numbers for our worldwide of fices are listed at the front of this manual.
© National Instruments Corporation G-1 NI 7831R User Manual Glossar y Symbol Pref ix V alue 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 Numbers/Symbols ° Degrees. > Greater than.
Glossary NI 7831R Use r Manual G-2 © National Instruments Corporation Square root of. +5V +5 VDC source signal. A A Amperes. A/D Analog-to-digital . A C Alternating curren t. ADC Analog-to-digital con verter—An elect ronic de vice, often an integrated circuit, that con verts an an alog v oltage to a digi tal number .
Glossary © National Instruments Corporation G-3 NI 7831R User Manual C CC e l s i u s . CalD AC Calibration D AC. CH Channel—Pin or wire lead to which you apply or from which you read the analog or digital signal. Anal og signals can be single-ended or differential.
Glossary NI 7831R Use r Manual G-4 © National Instruments Corporation DIO Digital input /output. DIO< i > Digital input/ou tput channel signal. DMA Direct memory access—A method by which data can be transferred to/from computer memory from/to a device or memory on the bus while the processor does something else.
Glossary © National Instruments Corporation G-5 NI 7831R User Manual I I/O Input/output—The transfer of data to/from a comput er system in volving communications channels, operator interface de vices, and/or data acquisition and control interfaces.
Glossary NI 7831R Use r Manual G-6 © National Instruments Corporation N noise An undesirable electrical signal—Nois e comes from external sources such as the A C power line, motors, generators, tra.
Glossary © National Instruments Corporation G-7 NI 7831R User Manual R RAM Random-access memory—The generic term for the read/write memory that is used in computers. RAM allows bits and bytes to be written to it as well as read from. V arious types of RA M are DRAM, EDO RAM, SRAM, and VRAM.
Glossary NI 7831R Use r Manual G-8 © National Instruments Corporation T THD T otal harmonic distortion—The rati o of the total rms signal due to harmonic distortion to the overall rms signal, in decibel or a percentage. thermocouple A temperature se nsor created by joining tw o diss imilar metals.
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 NI 7831R 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 NI 7831R - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso National Instruments NI 7831R imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul National Instruments NI 7831R ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il National Instruments NI 7831R, 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 NI 7831R.
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 NI 7831R. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo National Instruments NI 7831R 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.
