Allen-Bradley 1791-32B0 24V DC Input Module

Allen-Bradley 1791-32B0 32-Channel 24V DC Input Module

Product Introduction

The Allen-Bradley 1791-32B0 is a high-density Block I/O module. It offers 32 discrete input channels for 24V DC signals. You can use it in distributed I/O architectures. The module supports the Remote I/O (RIO) protocol. Each of the four groups holds eight channels. This design simplifies wiring and troubleshooting.

Technical Specifications

The 1791-32B0 operates with a nominal input voltage of 24V DC. Its on-state voltage range runs from 10 to 30V DC. Maximum off-state voltage is 5V DC. On-state current reaches 11 mA maximum at 30V DC. Minimum on-state current is 2.5 mA at 10V DC. Off-state current sits at 1.5 mA minimum.

Input impedance measures 3.4KΩ maximum. Switching performance is reliable for DC signals. External power supply needs 19.2 to 30V DC at 300 mA.

Additionally, the 1791-32B0 provides strong isolation. Power supply to remote I/O isolation is 500 VAC. I/O group-to-group isolation is also 500 VAC. I/O group-to-logic isolation reaches 500 VAC as well.

Mechanical and Environmental Parameters

This module works in standard industrial environments. You can mount it on a DIN rail. Its dimensions are 6.95 x 4.35 x 3.85 inches. The module weighs only 0.82 kg (1.81 lbs).

Power dissipation reaches 16.3 Watts maximum. Thermal dissipation is 55.6 BTU/hr. These ratings make it suitable for panel mounting without extra cooling.

Installation and Wiring

You can mount the 1791-32B0 on a DIN rail easily. Use 14 AWG stranded wire for I/O connections. Maximum insulation thickness is 3/64 inch. For the remote I/O link, use Belden 9463 cable.

Removable terminal strips sit on both left and right sides. They handle RIO, input, output, and power connections. Two switch assemblies let you configure key settings.

Specifically, you can set the I/O rack number, communication rate, starting I/O group, last state, and last chassis. Status indicators help you monitor I/O and communication states.

Compatibility Guidelines

The 1791-32B0 works with many controllers. Compatible models include the PLC-2, PLC-3, PLC-5/250, PLC-5 family, and SLC 5/02.

Furthermore, it works with 1771 series output modules. You must check two conditions. First, the output module's off-state leakage current must be less than the 1791-32B0 minimum off-state current (1.5 mA). Second, the minimum on-state voltage of the DC block input must exceed the supply voltage minus the voltage drop across the 1771 output module.

The module also works with pure coil 100-A45 contactors. It is compatible with Type F, Type P, and Type PH relays. For any external device, ensure its on-state voltage and current fall inside the 1791-32B0 on-state region. Similarly, off-state values must stay within the module's off-state region.

Communication Features

The 1791-32B0 uses the Remote I/O (RIO) protocol. This allows distributed I/O architecture over a single cable. You do not need a local chassis or power supply for each IO point.

Therefore, installation becomes faster and more cost-effective. The self-contained design includes signal conditioning, power regulation, and communication interface.

Packaging List

• 1791-32B0 module (1 unit)

• Removable terminal strips (left and right)

• DIN rail mounting clips

• Quick start user guide

Note: No certificates or warranty documents are included in the package.

Frequently Asked Questions (FAQ)

1. What voltage does the 1791-32B0 work with?
It works with 24V DC nominal. The acceptable range is 10 to 30V DC.

2. Can I use the 1791-32B0 with a PLC-5 controller?
Yes, it works with PLC-2, PLC-3, PLC-5/250, PLC-5 family, and SLC 5/02.

3. What cable do I need for the RIO link?
Use Belden 9463 cable for the remote I/O link connection.

4. How do I mount the 1791-32B0 module?
You can mount it on a DIN rail. The package includes mounting clips.

5. Which shipping carriers do you use?
We ship via FedEx, UPS, and DHL for fast and reliable delivery.