National Instruments RS485 - Manuals

© National Instruments Corp. 5 NI 9871 Operating Instructions Special Conditions for Marine Applications Some modules are Lloyd’s Register (LR) Type Approved for marine applications. To verify Lloyd’s Register certification, visit ni.com/certification and search for the LR certificate, or look for t...

© National Instruments Corp. 7 NI 9871 Operating Instructions The cables included with your kit convert the RJ-50 pinout to the standard NI pinout, as shown in Table 2. Table 2. Pin Assignments for RS485/RS422 DB-9 Male Connector Connector Pin Signal 1 GND 2 CTS+ 3 RTS+ 4 RXD+ 5 RXD– 6 CTS– 7 RTS– 8...

NI 9871 Operating Instructions 8 ni.com You must connect an external power supply to the NI 9871. This power supply provides the power for the RS485/RS422 transceivers on the module. You can use the included female four-position pigtail to connect to an external voltage source. Figure 1 lists the co...

© National Instruments Corp. 9 NI 9871 Operating Instructions Figure 2 shows the method of power connection to the NI 9871 module. Attach an isolated power supply to the V sup and COM terminals using the included pigtail. Figure 2. Powering the NI 9871 from an Isolated Power Source Figure 3 shows ho...

NI 9871 Operating Instructions 10 ni.com additional module. Ensure that the power supply can handle maximum power requirements for all modules connected. Caution All connections must be made before power is applied. Figure 3. Powering Multiple Modules from a Single Power Supply Red (+) Black (–) NI ...

© National Instruments Corp. 11 NI 9871 Operating Instructions RS485 Bus Topology and Termination Refer to Figure 4 and Figure 5 for an overview of 4-wire and 2-wire RS485 bus topologies and termination. Figure 4. 4-Wire Full-Duplex Multidrop Network Using Terminating Resistors Figure 5. 2-Wire Mult...

NI 9871 Operating Instructions 12 ni.com RS485 Transceiver Control Refer to Table 3 for a listing of TX and RX enable conditions for the different RS485 transceiver control modes. NI 9871 Hardware Overview The NI 9871 has four independent RS485/RS422 ports that are isolated from the other modules in...

© National Instruments Corp. 13 NI 9871 Operating Instructions Sleep Mode (CompactRIO Only) You can enable sleep mode for the CompactRIO system in software. In sleep mode, the system consumes less power and may dissipate less heat. Typically, when a system is in sleep mode, you cannot communicate wi...

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 maxSleep mode ................................. 50 ...

© National Instruments Corp. 15 NI 9871 Operating Instructions Safety Maximum Voltage 1 Connect only voltages that are within these limits. RS485/RS422 Port-to-COM ............. –8 to +13 VDC max, Measurement Category I V SUP -to-COM ................................... ±28 V max, Measurement Categor...

NI 9871 Operating Instructions 16 ni.com Isolation Voltages Port-to-earth ground Withstand.................................... 1000 V rms , verified by a dielectric withstand test, 5 s Continuous ................................. 60 VDC, Measurement Category I Hazardous Locations U.S. (UL) ............

© 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 electrical equipment for measurement, control, and laboratory use: • IEC 61010-1, EN 61010-1 • UL 61010-1, CSA 61010-1 Note For UL...

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. Note For EMC compliance, operate this device with shielded cabling. CE Compliance This product meets the essential requirements of applicable ...

© National Instruments Corp. 19 NI 9871 Operating Instructions Shock and Vibration To meet these specifications, you must panel mount 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 humidity............................... 5 to 95% RH, noncondensing Maximum altitude............................. 2,000 m Pollution Degree (IEC 60664) .......... 2 Environmental...

© National Instruments Corp. 21 NI 9871 Operating Instructions Waste Electrical and Electronic Equipment (WEEE) EU Customers At the end of their life cycle, all products must be sent to a WEEE recycling center. For more information about WEEE recycling centers and National Instruments WEEE initiativ...

NI 9871 Operating Instructions 22 ni.com Where to Go for Support The National Instruments Web site is your complete resource for technical support. At ni.com/support you have access to everything from troubleshooting and application development self-help resources to email and phone assistance from ...