Product Overview
The Allen-Bradley 1791-0A32 is a compact Block I/O module designed for high-density AC output applications. This industrial automation module delivers thirty-two (32) discrete AC output channels organized into four (4) groups of eight (8) channels each, making it an efficient solution for controlling multiple devices from a single remote I/O node. With its built-in Remote I/O (RIO) adapter capability, the 1791-0A32 operates as a distributed I/O station, communicating directly with RIO scanners in your control network.
Technical Specifications
The 1791-0A32 provides reliable AC switching performance across a wide operating range. Below are the key specifications for this Allen-Bradley module:
| Parameter |
Value |
| Manufacturer |
Allen-Bradley |
| Product Line |
1791 Block I/O |
| Module Type |
Digital AC Output Module |
| Number of Outputs |
32 |
| Channel Grouping |
4 groups of 8 channels |
| Operating Voltage Range |
20-132 VAC |
| Nominal Output Voltage |
120 VAC |
| Output Delay (OFF to ON) |
1.0 ms @ 60 Hz, 1.0 ms @ 50 Hz |
| Output Delay (ON to OFF) |
8.3 ms @ 60 Hz, 10.0 ms @ 50 Hz |
| OFF State Leakage Current |
3 mA |
| Maximum On-state Current |
50 mA per output |
| Surge Current |
10 A for 50 ms, repeatable every 2 sec |
| Max. On-state Voltage Drop |
1.5 V peak @ 300 mA |
| External Power |
85-132 VAC |
| Weight |
1.00 lbs (0.45 kg) |
| Lifecycle Status |
Discontinued / Obsolete |
Compatibility & Integration
The 1791-0A32 integrates seamlessly with a variety of Allen-Bradley programmable controllers. It supports the Remote I/O (RIO) protocol, enabling direct communication with RIO scanners. Compatible controllers include the PLC-2 family (with 1771-SN and 1772-SD/SD2 modules), PLC-3 family (with any scanner module and 1775-S5 or -SR5), and PLC-5 family (including PLC-5/20 and PLC-5VME 6008-LTV). This broad compatibility makes the 1791-0A32 a versatile choice for legacy and mixed-vendor automation systems.
Installation & Setup
Mounting the 1791-0A32 is straightforward with both vertical and horizontal orientation options. For vertical mounting, the maximum output current rating is 600 mA at 30°C or 300 mA at 60°C. For horizontal mounting, the rating is 300 mA at 30°C or 150 mA at 60°C. Power connections are made via terminals L1 (1), N (3), and GND (2), while RIO connections use terminals BLU (6), CLR (8), and SHD (7) on the left side. To set the I/O rack number, open the front cover, which also houses the I/O group switch assembly and status indicators for troubleshooting.
Applications
The 1791-0A32 can energize a wide range of output devices, including motor starters, solenoid-actuated devices, indicators, signaling devices, and other electrical loads. With a surge current rating of 10 A (1200 W) and a holding current of 300 mA (36 W) at 60°C (or 600 mA/72 W at 30°C), this module handles inrush currents effectively. Typical applications include remote machine control, material handling systems, and process control where distributed I/O reduces wiring costs.
Maintenance & Reliability
Operating temperature must stay between 0 and 60°C. The 1791-0A32 includes internal protection and an interior power supply, enhancing reliability. Given its discontinued status, proactive maintenance is essential. Regularly inspect the front cover status indicators, verify terminal connections, and ensure ambient temperature remains within limits to extend service life.
Selection Guide
Before purchasing, verify that the 1791-0A32 meets your output current requirements and that your controller supports RIO protocol. Since this model is discontinued, sourcing genuine units can be challenging. PLC Source PRO offers a reliable supply of this legacy module, backed by quality assurance. Contact us to confirm availability and ensure compatibility with your system.