Allen-Bradley 1771-ASB RIO Adapter Module

Allen-Bradley 1771-ASB Remote I/O Adapter Module

Product Introduction

The Allen-Bradley 1771-ASB module acts as the essential interface between your 1771 I/O chassis and the Remote I/O network. It efficiently links field devices to a PLC-5 processor. This adapter handles all communication requests from the RIO scanner. For instance, it translates serial data from the network into parallel data for the backplane. Consequently, it allows you to place I/O racks closer to your machinery. This strategic placement significantly reduces expensive and complex direct wiring.

Key Technical Specifications

This module offers flexible data transmission rates. You can set the communication speed to 57.6 kbit/s, 115 kbit/s, or 230 kbit/s. The maximum cable length depends on this baud rate. For example, it supports runs up to 10,000 feet at the lowest speed. Meanwhile, at the highest setting, it can reach up to 2,500 feet.

Furthermore, this 1771-ASB module requires a backplane current of 1.0 Amps at 5 Volts DC. It is compatible with 4, 8, 12, 16, or 32-slot 1771 I/O chassis. The module also provides support for both 1-slot and 2-slot I/O addressing. It uses a standard 1771-WB wiring arm for connections. Additionally, you must use Belden 9463 cable, commonly known as the "Blue Hose," for the RIO link. It also uses either 82 Ohm or 150 Ohm terminating resistors to close the network segment.

Mechanical and Environmental Parameters

The 1771-ASB is built for demanding industrial environments. It operates reliably within a temperature range of 32°F to 140°F (0°C to 60°C). For storage, it can withstand temperatures from -40°F to +185°F. Moreover, it is tolerant of humidity levels from 5% to 95% non-condensing. Its physical dimensions are 3.5 x 6.5 x 2.0 inches (89 x 165 x 51 mm). This compact design fits easily into the left-most slot of your chassis.

Diagnostic and Status Indicators

Troubleshooting is straightforward with this adapter. It has three diagnostic LEDs on its faceplate. The green ACTIVE light shows normal operation. Specifically, a red ADAPTER FAULT light alerts you to a communication issue. Likewise, the red I/O RACK FAULT indicator signals a problem with the backplane or connected modules. These indicators allow operators to quickly identify and resolve system issues.

Installation Guidelines

Proper installation ensures optimal performance. First, mount the 1771-ASB module in the first slot of your 1771 chassis. This is mandatory for its correct function. Next, set the two switch assemblies for the desired baud rate and chassis size. Then, connect the Belden 9463 cable to the RIO port. Remember to install the correct terminating resistor at both ends of the network segment. Finally, use the 1771-WB field wiring arm for making connections to your I/O modules.

Common Applications

This Allen-Bradley 1771-ASB adapter is a core component in many legacy and active automation systems. It is primarily used in manufacturing plants. For instance, it is perfect for connecting remote I/O racks in large conveyor systems. It is also used in material handling and packaging machinery. By centralizing control and decentralizing I/O, it simplifies system design. This makes it invaluable for system expansions or upgrades.

Network Topology and Termination

Remote I/O communication uses a daisy-chain topology. Both ends of this network segment require a terminating resistor. You can use either an 82 Ohm or a 150 Ohm resistor. The 150 Ohm type suits older configurations. Meanwhile, the 82 Ohm version is used for enhanced RIO network versions. This module supports up to 32 adapter devices on a single link. This capability provides substantial flexibility for large-scale automation projects.

Data Handling and Processing

The 1771-ASB module manages data in two distinct ways. It receives and sends data to the I/O scanner in serial form. However, it reads and writes data from input and output modules in parallel form. This dual-mode operation maximizes efficiency. It also improves overall system scan time significantly. Furthermore, it saves I/O image space by scanning all slots except the last four. This feature enhances the performance of your PLC-5 system.

Packaging List

• Allen-Bradley 1771-ASB RIO Adapter Module (1 unit)

• 1771-WB Field Wiring Arm (1 unit)

• Product Documentation (User Manual)

Shipping

We ship via FedEx, UPS, or DHL.

Frequently Asked Questions

1. What cable is required for the 1771-ASB module?

You must use Belden 9463 cable, often called the Belden "Blue Hose," for the Remote I/O link.

2. What is the maximum communication distance for this adapter?

The 1771-ASB supports a maximum cable length of 10,000 feet at 57.6 kbps. At 230.4 kbps, the maximum distance is 2,500 feet.

3. Which slot should I install this module in?

You must install the 1771-ASB in the left-most slot (slot 0) of the 1771 I/O chassis.

4. Does this module support 32-slot chassis?

Yes, it is compatible with 4, 8, 12, 16, and 32-slot 1771 I/O chassis configurations.

5. What do the red fault LEDs on this module indicate?

A red ADAPTER FAULT LED indicates a communication error between the scanner and the adapter. Meanwhile, the red I/O RACK FAULT LED signals an issue with the backplane or the connected I/O modules themselves.