National Instruments NI 9871, RS422, RS-485 User Manual

OPERATING INSTRUCTIONS AND SPECIFICATIONS

NI 9871

4-Port, RS485/RS422 Serial Module

This document describes how to use the National Instruments 9871 and includes specifications and pin assignments for the NI 9871. Vis it ni.com/info and enter rdsoftwareversion to determine which software you need for the modules you are using. For information about installing, configuring, and programming the system, refer to the system documentation. Visit enter

cseriesdoc for information about C Series documentation.

Note The safety guidelines and specifications in this

ni.com/info and

document are specific to the NI 9871. The other components in the system might not meet the same safety ratings and specifications. Refer to the documentation for each component in the system to determine the safety ratings and specifications for the entire system. Visit

ni.com/info and enter cseriesdoc for information

about C Series documentation.

Safety Guidelines

Operate the NI 9871 only as described in these operating instructions.

Hot Surface This icon denotes that the component may be

hot. Touching this component may result in bodily injury.

NI 9871 Operating Instructions 2 ni.com

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. Follow these guidelines if you are installing the NI 9871 in a potentially explosive environment. Not following these guidelines may result in serious injury or death.

Caution Do not disconnect I/O-side wires or connectors

unless power has been switched off or the area is known to be nonhazardous.

Caution Do not remove modules unless power has been

switched off or the area is known to be nonhazardous.

Caution Substitution of components may impair

suitability for Class I, Division 2.

Caution For Zone 2 applications, install the

CompactRIO system in an enclosure rated to at least IP 54 as defined by IEC 60529 and EN 60529.

Caution For Zone 2 applications, install a protection

device between the RS485/RS422 signal cables and the NI 9871 RJ-50 jacks (ports 1– 4). The device must prevent the RS485/RS422 signal-to-signal or signal-to-COM voltage from exceeding 23 V if there is a transient overvoltage condition.

Caution For Zone 2 applications, install a protection

device between the external power supply and the NI 9871 V V

-to-COM voltage from exceeding 39 V if there is a

sup

and COM pins. The device must prevent the

sup

transient overvoltage condition.

Special Conditions for Hazardous Locations in Europe

This equipment has been evaluated as Ex nA IIC T4 equipment under DEMKO Certificate No. 07 ATEX 0626664X. Each module is marked 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 must use the device in an NI chassis or controller that has been evaluated as EEx nC IIC T4, Ex nA IIC T4, or Ex nL IIC T4 equipment.

NI 9871 Operating Instructions 4 ni.com

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 the Lloyd’s Register mark on the module.

Caution To meet radio frequency emission requirements

for marine applications, use shielded cables and install the system in a metal enclosure. Suppression ferrites must be installed on power supply inputs near power entries to modules and controllers. Power supply and module cables must be separated on opposite sides of the enclosure and must enter and exit through opposing enclosure walls.

Wiring the NI 9871

The NI 9871 has four RJ-50 receptacles that provide connections for four RS485/RS422 devices.

Table 1. RS485/RS422 Port Pinout

RJ50 Jack

* These signals are shared by all four RJ-50 connectors on the NI 9871.

NI 9871 Operating Instructions 6 ni.com

RJ-50 Pin Signal Name*

1 No Connect

2 TXD–

3 TXD+

TXD–

TXD+

RTS–

CTS–

RXD–

RXD+

RTS+

CTS+

COM

4 RTS –

5 CTS–

6 RXD–

7 RXD+

8 RTS +

9 CTS+

10 GND

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 RT S+

6 7 8 9

1 2 3 4 5

4 RXD+

5 RXD–

6 CTS–

7 RT S–

8 TXD+

9 TXD–

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.

SUP

3 COM 4COM

Figure 1. Four-Position External Power Connector

NI 9871 Operating Instructions 8 ni.com

Figure 2 shows the method of power connection to the NI 9871 module. Attach an isolated power supply to the V

and COM

sup

terminals using the included pigtail.

Red (+) V+ V–

Any 8 - 28 V

Isolated

Power Supply

NI P/N 198159-XX:

Female Microfit

Black (–)

Pigtail

Figure 2. Powering the NI 9871 from an Isolated Power Source

Figure 3 shows how to use the optional y-adapter (available at

ni.com/serial) to connect power to more than one module

using the same power source. One y-adapter is needed for each

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.

NI P/N 198159-XX:

Female Microfit

Pigtail

Red (+)

V+ V–

Any 8 - 28 V

Isolated

Power Supply

NI P/N 198303-XX:

Male Microfit

Figure 3. Powering Multiple Modules from a Single Power Supply

NI 9871 Operating Instructions 10 ni.com

Black (–)

Y-Adapter

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.

MASTER

120 Ω

Slave 1

Slave 2 Slave n

120 Ω

Figure 4. 4-Wire Full-Duplex Multidrop Network Using Terminating Resistors

MASTER

120 Ω

Slave 1

Slave 2 Slave n

120 Ω

Figure 5. 2-Wire Multidrop Network Using Terminating Resistors

RS485 terminators are available at ni.com/serial.

RS485 Transceiver Control

Refer to Table 3 for a listing of TX and RX enable conditions for the different RS485 transceiver control modes.

Table 3. Transceiver Control Pin Conditions

2-Wire

Enable 4-Wire

TX On DTR DTR TX

RX On On DTR# TX#

DTR/Echo DTR/No Echo Auto

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 12 ni.com

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 with the modules. Refer to the Specifications section for more information about power consumption and thermal dissipation.

Specifications

The following specifications are typical for the range –40 to 70 °C unless otherwise noted.

Maximum baud rate.......................... 3.6864 Mbps

Maximum cable length ..................... 1.2 km (4,000 ft.)

Data line ESD protection

(human body model)......................... ±15 kV

MTBF ............................................... 514,016 hours at 25 °C;

Bellcore Issue 6, Method 1, Case 3, Limited Part Stress Method

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 ................................. 50 μW max

Thermal dissipation (at 70 °C)

Active mode ............................... 1.5 W max

Sleep mode ................................. 55 mW max

Required external supply voltage range (V

Power supply consumption from external supply V

) ......................... +8 to +28 VDC

SUP

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 14 ni.com

Safety

Maximum Voltage

Connect only voltages that are within these limits.

RS485/RS422 Port-to-COM............. –8 to +13 VDC max,

-to-COM ................................... ±28 V max,

SUP

Measurement Category I is for measurements performed on circuits not directly connected to the electrical distribution system referred to as MAINS voltage. MAINS is a hazardous live electrical supply system that powers equipment. This category is for measurements of voltages from specially protected secondary circuits. Such voltage measurements include signal levels, special equipment, limited-energy parts of equipment, circuits powered by regulated low-voltage sources, and electronics.

Caution Do not connect to signals or use for

measurements within Measurement Categories II, III, or IV.

The maximum voltage that can be applied or output without creating a safety hazard.

Measurement Category I

Isolation Voltages

Port-to-earth ground

Withstand.................................... 1000 V

, verified by a

rms

dielectric withstand test, 5 s

Continuous ................................. 60 VDC,

Measurement Category I

Hazardous Locations

U.S. (UL) .......................................... Class I, Division 2,

Groups A, B, C, D, T4; Class I, Zone 2, AEx nA II T4

Canada (C-UL) ................................. Class I, Division 2,

Europe (DEMKO)............................. Ex nA IIC T4

NI 9871 Operating Instructions 16 ni.com

Groups A, B, C, D, T4; Class I, Zone 2, Ex nA II 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

Note For UL and other safety certifications, refer to the

product label, or visit

ni.com/certification, search

by model number or product line, and click the appropriate link in the Certification column.

Electromagnetic Compatibility

Emissions.......................................... EN 55011 Class A at 10 m

Immunity........................................... Industrial levels per

EMC/EMI ......................................... CE, C-Tick, and FCC Part 15

FCC Part 15A above 1 GHz

EN 61326-1:1997 + A2:2001, Table A.1

(Class A) Compliant

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 European Directives, as amended for CE marking, as follows:

Low-Voltage Directive (safety)......... 2006/95/EC

Electromagnetic Compatibility

Directive (EMC) ............................... 2004/108/EC

Online Product Certification

Refer to the product Declaration of Conformity (DoC) for additional regulatory compliance information. To obtain product certifications and the DoC for this product, visit

certification

, search by module number or product line, and

click the appropriate link in the Certification column.

NI 9871 Operating Instructions 18 ni.com

ni.com/

Shock and Vibration

To meet these specifications, you must panel mount the CompactRIO system.

Operating vibration,

random (IEC 60068-2-64) ................ 5 g

, 10 to 500 Hz

rms

Operating shock

(IEC 60068-2-27).............................. 30 g, 11 ms half sine,

50 g, 3 ms half sine, 18 shocks at 6 orientations

Operating vibration,

sinusoidal (IEC 60068-2-6) ..............5 g, 10 to 500 Hz

Environmental

CompactRIO modules are intended for indoor use only. For outdoor use, mount the CompactRIO system in a suitably rated enclosure. Refer to the installation instructions for the chassis you are using for more information about meeting these specifications.

Operating temperature ...................... – 40 to 70 °C

Storage temperature .......................... –40 to 85 °C

Ingress protection.............................. IP 40

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 Management

NI is committed to designing and manufacturing products in an environmentally responsible manner. NI recognizes that eliminating certain hazardous substances from our products is beneficial to the environment and to NI customers.

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 20 ni.com

ni.com/environment. This page

Waste Electrical and Electronic Equipment (WEEE)

⬉ᄤֵᙃѻક∵ᶧ᥻ࠊㅵ⧚ࡲ⊩ ˄Ё೑

Ё೑ᅶ᠋

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 initiatives, visit

environment/weee.htm

ni.com/

RoHS

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National Instruments

National InstrumentsЁ೑RoHS

ni.com/environment/rohs_china

about China RoHS compliance, go to

environment/rohs_china

ヺড়Ё೑⬉ᄤֵᙃ

Ǆ݇Ѣ

(RoHS)

ড়㾘ᗻֵᙃˈ䇋ⱏᔩ

(For information

ni.com/

Where to Go for Support

The National Instruments Web site is your complete resource for technical support. At everything from troubleshooting and application development self-help resources to email and phone assistance from NI Application Engineers.

National Instruments corporate headquarters is located at 11500 North Mopac Expressway, Austin, Texas, 78759-3504. National Instruments also has offices located around the world to help address your support needs. For telephone support in the United States, create your service request at and follow the calling instructions or dial 512 795 8248. For telephone support outside the United States, contact your local branch office:

Australia 1800 300 800, Austria 43 662 457990-0, Belgium 32 (0) 2 757 0020, Brazil 55 11 3262 3599, Canada 800 433 3488, China 86 21 5050 9800, Czech Republic 420 224 235 774, Denmark 45 45 76 26 00, Finland 358 (0) 9 725 72511, France 01 57 66 24 24, Germany 49 89 7413130, India 91 80 41190000, Israel 972 3 6393737, Italy 39 02 41309277, Japan 0120-527196,

NI 9871 Operating Instructions 22 ni.com

ni.com/support you have access to

ni.com/support

Korea 82 02 3451 3400, Lebanon 961 (0) 1 33 28 28, Malaysia 1800 887710, Mexico 01 800 010 0793, Netherlands 31 (0) 348 433 466, New Zealand 0800 553 322, Norway 47 (0) 66 90 76 60, Poland 48 22 3390150, Portugal 351 210 311 210, Russia 7 495 783 6851, Singapore 1800 226 5886, Slovenia 386 3 425 42 00, South Africa 27 0 11 805 8197, Spain 34 91 640 0085, Sweden 46 (0) 8 587 895 00, Switzerland 41 56 2005151, Taiwan 886 02 2377 2222, Thailand 662 278 6777, Turkey 90 212 279 3031, United Kingdom 44 (0) 1635 523545

National Instruments, NI, ni.com, and LabVIEW are trademarks of National Instruments Corporation. Refer to the Terms of Use section on product and company names mentioned herein are trademarks or trade names of their respective companies. For patents covering National Instruments products/technology, refer to the appropriate location: Help»Patents in your software, the

ni.com/patents.

ni.com/legal for more information about National Instruments trademarks. Other

patents.txt file on your media, or the National Instruments Patent Notice at

372277B-01 Sep08

National Instruments NI 9871, RS422, RS-485 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Safety Guidelines

Safety Guidelines for Hazardous Locations

Special Conditions for Hazardous Locations in Europe

Special Conditions for Marine Applications

Wiring the NI 9871

Table 1. RS485/RS422 Port Pinout

Table 2. Pin Assignments for RS485/RS422 DB-9 Male Connector

Figure 1. Four-Position External Power Connector

Figure 2. Powering the NI 9871 from an Isolated Power Source

Figure 3. Powering Multiple Modules from a Single Power Supply

RS485 Bus Topology and Termination

Figure 4. 4-Wire Full-Duplex Multidrop Network Using Terminating Resistors

Figure 5. 2-Wire Multidrop Network Using Terminating Resistors

RS485 Transceiver Control

Table 3. Transceiver Control Pin Conditions

NI 9871 Hardware Overview

Sleep Mode (CompactRIO Only)

Specifications

Power Requirements

Physical Characteristics

Safety

Maximum Voltage

Isolation Voltages

Hazardous Locations

Safety Standards

Electromagnetic Compatibility

CE Compliance

Online Product Certification

Shock and Vibration

Environmental

Environmental Management

Where to Go for Support