Manuale d’uso / di manutenzione del prodotto RS422 del fabbricante National Instruments
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OPERATING INSTRUCTIONS AND S PECIFICATIONS NI 9871 4-Port, RS485/RS42 2 Serial Modu le.
NI 9871 Operating Instructions 2 ni.com This document describes how to use the National Instruments 9871 and includes specif icat ions and pin assignments for the NI 9871. Vi s i t ni.com/info and enter rdsoftwareversion to determine which software you need for the modules you are using.
© National Instruments Corp. 3 NI 9871 Operating Instructions Safety Guidelines fo r Hazardous Loca tions The NI 9871 is suitable for use in Cl ass I, Division 2, Groups A, B, C, D, T4 hazardous locations; Clas s I, Zone 2, AEx nA II T4 and Ex nA II T4 hazardous locations ; and nonhazardous locations only .
NI 9871 Operating Instructions 4 ni.com Caution For Zone 2 applications, install a protection device between the RS485/RS 422 signal cables and the NI 9871 RJ-50 jacks (p orts 1– 4). The device must prev ent the RS485/RS422 signal-to -signal or signal-to-COM voltage from ex ceeding 23 V if there is a transient overv oltage condition.
© National Instruments Corp. 5 NI 9871 Operating Instructions Special Conditions fo r Marine Appli cations Some modules are Lloyd’ s Register (LR) T ype Approved for marine applications.
NI 9871 Operating Instructions 6 ni.com Wiring the NI 9871 The NI 9871 has four RJ-50 recep t acles that prov ide connections for four RS485/RS422 de vices.
© National Instruments Corp. 7 NI 9871 Operating Instructions The cables included with your kit con vert the RJ-50 pinout to the standard NI pinout, as shown in T able 2.
NI 9871 Operating Instructions 8 ni.com Y ou must connect an external po wer supply to the NI 9871. This power supply p rovides the po wer for the RS485/RS422 transceiv ers on th e module. Y ou can use the included female four-position pigtail to connect to an e xternal vo ltage source.
© National Instruments Corp. 9 NI 9871 Operating Instructions Figure 2 shows the method of po wer connection to the NI 9871 module. Attach an isolated power supply to the V sup and C OM terminals using the included pigtail.
NI 9871 Operating Instructions 10 ni.com additional module. Ensure that the power supply can handle maximum power requirements for all modules connected.
© National Instruments Corp. 11 NI 9871 Operating Instructions RS485 Bus T opology and T ermi nation Refer to Figure 4 and Fig ure 5 for an o vervie w of 4-wire and 2-wire RS485 bus topol ogies and termination. Figure 4. 4-Wir e Full-Dupl ex Multidrop Netw ork Using T erminating Resistors Figure 5.
NI 9871 Operating Instructions 12 ni.com RS485 T ransceiver Control Refer to T able 3 for a listing of TX and RX enable conditions for the dif ferent RS485 transcei ver contro l modes. NI 9871 Hardware Over view The NI 9871 has four independent RS48 5/RS422 ports that are isolated from the other modules in the system.
© National Instruments Corp. 13 NI 9871 Operating Instructions Sleep Mode (CompactRIO Only) Y ou can enable sleep mode fo r the CompactRIO system in software. In sleep mode, the syst em consumes less power and may dissipate less heat. T ypically , when a system is in sleep mode, you cannot communicate with th e modules.
NI 9871 Operating Instructions 14 ni.com Note Contact NI for Bellcore MTBF specifications at other temperatures or for MIL-HDBK -217F specifications. Power Requirements Power consumption from chassis Active mode ............ ........... ........ 0.5 W max Sleep mode .
© National Instruments Corp. 15 NI 9871 Operating Instructions Safety Maximum Voltage 1 Connect only v oltages that are within these limits. RS485/RS422 Port-to-COM ........ ..... –8 to +13 VDC max, Measurement Category I V SUP -to-COM ............
NI 9871 Operating Instructions 16 ni.com Isolation Voltages Port-to-earth ground W ithstand............... ......... ............ 1000 V rms , ver ifie d by a dielectric withstand test, 5 s Continuous .......... ........... ......... ... 60 VDC, Measurement Category I Hazardous Locations U.
© National Instruments Corp. 17 NI 9871 Operating Instructions Safety Standards The NI 9871 is designed to meet the requirements of the following standards of safety for electric al equipment for mea.
NI 9871 Operating Instructions 18 ni.com Note For the standards applied to assess the EMC of this product, refer to the Online Product Certification section.
© National Instruments Corp. 19 NI 9871 Operating Instructions Shock and Vibration T o meet these spec ifications, you must panel mou nt the CompactRIO system . Operating vibration, random (IEC 60068-2-64) ... ............. 5 g rms , 10 to 500 Hz Operating shock (IEC 60068-2-27).
NI 9871 Operating Instructions 20 ni.com Operating humidity ............. ........... ... 10 to 90% RH, noncondensing Storage humid ity ........ ........... ........... . 5 to 95% RH, noncondensing Maximum altitude.......... ......... .......... 2,000 m Pollution Degree (IEC 60664) .
© National Instruments Corp. 21 NI 9871 Operating Instructions Waste Electrical and Electronic Equipment (WEEE) EU Customers At the end of their lif e cycle, all products must be sent to a WEEE re c ycling center . For more information about WEEE recy cling centers and National Instruments WEEE initi ativ es, visi t ni.
NI 9871 Operating Instructions 22 ni.com Where to Go for Support The National Instruments W eb site is your complete resource for technical support. At ni.com/support you ha ve access to ev erything from troubleshooting and application de velopment self-help resources to emai l and phone assistance from NI Application Engineers.
© National Instruments Corp. 23 NI 9871 Operating Instructions K orea 82 02 3451 3400, Lebanon 961 (0) 1 33 28 28, Malaysia 1800 887710, Mexico 0 1 800 010 0793, Netherlands 31 (0) 348 433 466, New Z.
© 2007–2008 Nati onal Instruments Corp. All rights reserved. 372277B-01 Sep08 National Instruments, NI, n i.com, and LabVIEW are trademarks of National Instrument s Corporation. Refer to the Terms of Use section on ni.com/legal for more information about National Instrument s trademarks.
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 RS422 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 RS422 - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso National Instruments RS422 imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul National Instruments RS422 ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il National Instruments RS422, 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 RS422.
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 RS422. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo National Instruments RS422 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.