Allen-Bradley 1746-IN16 SLC 500 16-Point AC/DC Input Module

June 30, 2026 • 2 min read • wayne • Guide

Product Summary

The Allen-Bradley 1746-IN16 is a robust SLC 500 digital input module. It offers sixteen sinking channels for both 24V AC and DC signals. This module provides reliable status feedback via per-channel LEDs. It occupies just one slot in any 1746 chassis.

Expert Technical Evaluation & Performance Review

This module processes sixteen discrete input signals with sinking logic. It accepts a wide voltage range from 10 to 30 Volts AC or DC. Engineers value this flexibility for mixed-signal environments. The module draws only 0.085 A from the 5V backplane. This low current draw minimizes power supply loading.

The signal delay varies based on your input type. For DC voltage, the module switches in 15 ms for both transitions. For AC voltage, the delay extends to 25 ms. This difference allows for proper AC signal debouncing. Each channel requires only 8 mA of nominal input current. The total module power dissipation is just 6 Watts.

Every channel features a dedicated LED indicator for status. This LED confirms that the field signal reaches the module. It serves as a critical troubleshooting tool for technicians. The module uses a standard 1746-HT or 1746-HCA I/O connection cable. This ensures secure and reliable wiring to field devices.

Step-by-Step User & Installation Guide

First, ensure the SLC 500 chassis power is off. Align the 1746-IN16 module with an open single slot. Push the module firmly onto the chassis backplane connectors. The male connectors will engage with the integrated bus. Secure the module using the top and bottom locking tabs.

Next, connect your field wiring using the proper cable. Use the 1746-HT or 1746-HCA cable for reliable connections. Wire your sinking input devices to the terminal assignments. Verify that your voltage source matches the 24V AC or DC range. Apply power to the module only after all wiring is complete.

Finally, power up the SLC 500 system and check the LEDs. Each active input channel should show a solid LED. Test each channel by actuating the connected field device. Monitor the input status in your PLC program. The module will respond within its specified signal delay times.