This document describes how to use the National Instruments 9871 and includes specifications and pin assignments for the NI 9871. Visit ni.com/info which software you need for the modules you are using. For information about installing, configuring, and programming the system, refer to the system documentation.
Safety Guidelines for Hazardous Locations The NI 9871 is suitable for use in Class I, Division 2, Groups A, B, C, D, T4 hazardous locations; Class I, Zone 2, AEx nA II T4 and Ex nA II T4 hazardous locations; and nonhazardous locations only.
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II 3G and is suitable for use in Zone 2 hazardous locations. If you are using the NI 9871 in Gas Group IIC hazardous locations or in ambient temperatures of –40 °C ≤ Ta ≤ 70 °C, you...
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The NI 9871 has four RJ-50 receptacles that provide connections for four RS485/RS422 devices. Table 1. RS485/RS422 Port Pinout * These signals are shared by all four RJ-50 connectors on the NI 9871. NI 9871 Operating Instructions RJ-50 Pin RJ50 Jack TXD–...
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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 connections between an external voltage source (of +8 V to +28 V) and the NI 9871.
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Figure 2 shows the method of power connection to the NI 9871 module. Attach an isolated power supply to the V and COM terminals using the included pigtail. Red (+) V– Black (–) Any 8 - 28 V Isolated Power Supply...
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V– Any 8 - 28 V Isolated Power Supply NI P/N 198303-XX: Male Microfit Y-Adapter Figure 3. Powering Multiple Modules from a Single Power Supply NI 9871 Operating Instructions NI P/N 198159-XX: Female Microfit Pigtail Red (+) Black (–) ni.com...
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Table 3. Transceiver Control Pin Conditions Enable 4-Wire NI 9871 Hardware Overview The NI 9871 has four independent RS485/RS422 ports that are isolated from the other modules in the system. Each port is fully compatible with the ANSI/EIA/TIA-485 standard. NI 9871 Operating Instructions...
Typical ... 1 W Maximum ... 3.5 W Physical Characteristics If you need to clean the module, wipe it with a dry towel. Weight... Approx. 153 g (5.4 oz) NI 9871 Operating Instructions ) ... +8 to +28 VDC ni.com...
Hazardous Locations U.S. (UL) ... Class I, Division 2, Canada (C-UL) ... Class I, Division 2, Europe (DEMKO)... Ex nA IIC T4 NI 9871 Operating Instructions , verified by a dielectric withstand test, 5 s Measurement Category I Groups A, B, C, D, T4;...
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 For UL and other safety certifications, refer to the...
Refer to the product Declaration of Conformity (DoC) for additional regulatory compliance information. To obtain product certifications and the DoC for this product, visit , search by module number or product line, and certification click the appropriate link in the Certification column. NI 9871 Operating Instructions ni.com/ ni.com...
For additional environmental information, refer to the NI and the Environment Web page at contains the environmental regulations and directives with which NI complies, as well as other environmental information not included in this document. NI 9871 Operating Instructions noncondensing noncondensing ni.com/environment . This page...
Where to Go for Support The National Instruments Web site is your complete resource for technical support. At you have access to ni.com/support everything from troubleshooting and application development self-help resources to email and phone assistance from NI Application Engineers.
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National Instruments, NI, ni.com, and LabVIEW are trademarks of National Instruments Corporation. Refer to the Terms of Use section on ni.com/legal for more information about National Instruments trademarks. Other product and company names mentioned herein are trademarks or trade names of their respective companies.
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