Allen-Bradley 1791-32A0 Input Module

Allen-Bradley 1791-32A0 32-Channel 120VAC Input Module

Product Introduction

The Allen-Bradley 1791-32A0 is a high-density Block I/O module. It offers 32 discrete input channels for 120VAC 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 1791-32A0 operates with an input voltage of 120VAC. Its on-state voltage range runs from 79 to 132VAC at 47–63 Hz. The nominal input current is 11 mA. Maximum on-state current reaches 12.3 mA at 132VAC. Off-state voltage stays below 35V maximum. Off-state current is 2.3 mA minimum.

Input impedance measures 15KΩ at 60 Hz. Switching delays are predictable. The off-to-on transition takes only 1.0 ms. On-to-off transition takes up to 26 ms. This allows a half-cycle dropout tolerance. External power supply needs 85–132VAC at 150 mA.

Additionally, the 1791-32A0 provides strong isolation. I/O group-to-group isolation is 1250 VAC. I/O group-to-logic isolation is also 1250 VAC. Power supply to RIO port isolation reaches 500 VAC.

Mechanical and Environmental Parameters

This module works in tough industrial settings. Its operating temperature ranges from 0 to 60°C. Storage temperature spans -40 to 85°C. Relative humidity can be 5–95% non-condensing.

Power dissipation reaches 13.62 Watts maximum. Thermal dissipation is 46.44 BTU/hr. The module weighs only 0.91 kg (2.00 lbs). Its dimensions are 6.95 x 4.35 x 3.85 inches.

Installation and Configuration

You can mount the 1791-32A0 on a DIN rail or a panel. Use 14 gauge stranded wire for connections. Maximum insulation thickness is 3/64 inch. Two switch assemblies let you configure key settings.

Specifically, you can set the starting I/O group, last chassis, I/O rack number, last state, and communication rate. Removable terminal strips sit on both left and right sides. They handle RIO, input, output, and power connections. Status indicators help you monitor communication and I/O states.

Communication and Compatibility

The 1791-32A0 uses the Remote I/O (RIO) protocol. It works with many controllers. Compatible models include the PLC-2, PLC-3, PLC-5/250, PLC-5 family, and SLC 5/02. This makes it a flexible choice for legacy and modern systems.

Furthermore, its self-contained design includes a power supply, signal conditioning, and I/O connections. You do not need extra chassis or adapters. Therefore, installation is fast and cost-effective.

Packaging List

• 1791-32A0 module (1 unit)

• Removable terminal strips (left and right)

• DIN rail mounting clips

• User manual quick start guide

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

Frequently Asked Questions (FAQ)

1. What controllers work with the 1791-32A0?
It works with PLC-2, PLC-3, PLC-5/250, PLC-5 family, and SLC 5/02 controllers via RIO.

2. Can I use the 1791-32A0 in a high-vibration environment?
Yes, its operating temperature range and mounting options suit industrial floors with moderate vibration.

3. What happens if input voltage drops below 79VAC?
The channel may turn off because 79VAC is the minimum on-state voltage. Check your supply.

4. How do I set the communication rate on this module?
Use the two switch assemblies on the module. Follow the manual to select the correct baud rate.

5. Which shipping carriers do you use for the 1791-32A0?
We ship via FedEx, UPS, and DHL for fast and reliable delivery worldwide.