1746-IA16 | Allen-Bradley Digital AC Input Module Supplier

What Is the 1746-IA16?

When your SLC 500 system needs to reliably sense AC signals from push buttons, limit switches, or proximity sensors, the 1746-IA16 delivers a straightforward solution. This Allen-Bradley Digital AC Input Module accepts 85-132 Volts AC across sixteen input channels, making it a versatile choice for general-purpose discrete input applications. Designed to occupy a single slot in the SLC 500 chassis, the module integrates seamlessly into both fixed and modular controller configurations.

As part of the SLC 500 series from Rockwell Automation, the 1746-IA16 provides a real-time interface between field devices and the controller. It captures the state of each input and passes that data to the processor during the input scan cycle. Without accurate input detection, the controller cannot execute its logic correctly, so this module plays a critical role in system performance.

Key Features & Technical Specs

• Sixteen (16) input channels accept AC signals from 85 to 132 Volts AC.
• Backplane current consumption is 85 milliamps at 5 Volts DC.
• Signal delay is 35 milliseconds ON and 45 milliseconds OFF.
• Off-state current is 2 milliamps maximum.
• Off-state voltage is 50 Volts AC maximum.
• Step response is 100 milliseconds in and 2.5 milliseconds out.
• I/O connection uses 1746-HT and 1746-HCA terminal blocks.

One distinctive spec is the 35 ms ON delay and 45 ms OFF delay. This ensures the module filters out short transients, preventing false triggering from electrical noise. In environments with motor starters or contactors, this built-in filtering improves system reliability without additional components.

Applications & Use Cases

In manufacturing lines, the 1746-IA16 monitors the status of conveyor belt sensors and start/stop push buttons. For packaging machinery, it detects product presence before the controller activates wrapping or sealing. The module also suits material handling systems where limit switches signal pallet positions. Because it handles 85-132 VAC inputs, it works directly with standard industrial AC sensors without extra signal conditioning.

Installation & Setup

Mount the 1746-IA16 into any available slot of the SLC 500 chassis. The module uses a removable terminal block, so you can replace the module without rewiring field connections. Connect AC input devices to the 20 terminals, with terminals 18 and 19 serving as internally connected commons. Ensure each input device is compatible with the SLC 500 input circuit inrush current, which has a maximum duration of 500 microseconds and a maximum current of 0.8 mA. No internal protection circuitry is provided, so external fusing may be necessary per your system design.

Maintenance & Reliability

Routine inspection of the 1746-IA16 should include verifying that all terminal connections remain tight and free of corrosion. Check that the chassis slot is clean and that the module is fully seated. The module’s solid-state design has no moving parts, reducing wear over time. Environmental factors such as temperature and humidity should stay within the SLC 500 system specifications to ensure long-term reliability.

Compatibility & Integration

The 1746-IA16 integrates with any SLC 500 processor, including fixed and modular controller styles. It can be installed in the local chassis or in an expansion rack. The module uses 1746-HT and 1746-HCA I/O connections for field wiring. No special software configuration is required beyond addressing the module in the I/O configuration of your programming software.

FAQs about the 1746-IA16

Q: What is the input voltage range of the 1746-IA16?

A: The input voltage range is 85-132 Volts AC.

Q: How many inputs does the 1746-IA16 have?

A: It has sixteen (16) input channels.

Q: What is the backplane current consumption?

A: The backplane current consumption is 85 milliamps at 5 Volts DC.

Q: What are the signal delay times?

A: The ON delay is 35 milliseconds, and the OFF delay is 45 milliseconds.

Q: Does the module include internal protection circuitry?

A: No, the 1746-IA16 does not offer internal protection circuitry.

Product Support & Availability

The 1746-IA16 is in stock and ready to ship from Petro Auto Tech. Contact our team for current pricing and lead times. We provide fast, reliable service for industrial automation parts.