Product Overview

The Allen-Bradley 1746-IM16 is a high-density discrete input module designed for the SLC 500™ platform. This module provides 16 isolated channels capable of interfacing high-voltage AC field signals directly with the PLC backplane. Operating at a nominal voltage of 200/240V AC, it is specifically engineered for monitoring heavy industrial machinery, motor starter auxiliary contacts, and presence sensors that operate on standard utility-level voltages.

By utilizing this module, system integrators can eliminate the need for interposing relays when sensing high-voltage circuits, thereby reducing cabinet complexity and points of failure. The 1746-IM16 is compatible with any local or expansion slot in an SLC 500 chassis and is recognized for its superior noise immunity and electrical isolation, ensuring that high-voltage transients on the factory floor do not compromise the integrity of the controller’s logic.

Technical Performance and Safety Features

The 1746-IM16 is built for durability and precision in electrically noisy environments.

• High-Voltage Versatility: Supports an expansive input range of 170V to 265V AC, accommodating fluctuations in industrial power grids.

• Enhanced Electrical Isolation: Features a tested isolation voltage of 1500V AC between the field-side wiring and the backplane logic to protect the CPU and other sensitive modules.

• Maintenance Efficiency: Equipped with a Removable Terminal Block (RTB), allowing for module replacement without disconnecting individual field wires, which significantly reduces downtime during service.

• Signal Filtering: Integrated digital filtering provides an OFF-to-ON delay of 35ms and an ON-to-OFF delay of 45ms to ensure stable state detection and eliminate "chatter" from mechanical contacts.

Technical Specifications

• Manufacturer: Allen-Bradley (Rockwell Automation)

• Model Number: 1746-IM16

• Module Type: Digital AC Input

• Number of Inputs: 16 Points

• Nominal Voltage: 200/240V AC

• Operating Voltage Range: 170–265V AC @ 47–63 Hz

• Backplane Current Draw: 85 mA @ 5V DC; 0 mA @ 24V DC

• Maximum Off-State Voltage: 50V AC

• Nominal Input Current: 12 mA @ 240V AC

• Operating Temperature: 0°C to 60°C (32°F to 140°F)

• Dimensions: 3.5 x 13.0 x 14.5 cm

• Weight: 0.9 kg

Application and System Compatibility

• Motor Control Centers (MCC): Monitoring the status of 240V AC contactors and disconnected switches.

• Facility Management: Interfacing with high-voltage HVAC sensors and lighting control circuits.

• Heavy Manufacturing: Detecting limits and positions on large-scale assembly equipment powered by 240V AC.

• Legacy Integration: Seamlessly works with SLC 5/01, 5/02, 5/03, 5/04, and 5/05 processors in modular chassis configurations.