Digital Input Module | Allen-Bradley 1794-IC16 FLEX I/O

The Allen-Bradley 1794-IC16 is a 16-point 48 V DC sink digital input module designed for the FLEX I/O distributed system. It senses discrete ON/OFF signals from field instruments, switches, and sensors, translating DC status levels into digital data over the system backplane. Featuring non-isolated sinking inputs and logic-driven channel indicators, it expands remote input capacity in industrial control architectures.

Input Characteristics and Signal Handling

The module provides 16 non-isolated sinking inputs operating at a nominal 48 V DC rating. It accepts ON-state voltages ranging from 30 V DC to 60 V DC with input current levels between 2.0 mA and 7.0 mA, maintaining a nominal input impedance of 11 kΩ. Programmable input filter times allow customization to suppress signal noise and contact bounce based on field application requirements.

Backplane Integration and Installation

The 1794-IC16 mounts directly onto compatible FLEX I/O terminal base units, such as the 1794-TB3S or 1794-TB3SK, using a 2-position keyswitch setup for mechanical alignment. The terminal base handles field wiring terminations, permitting module removal and insertion under power (RIUP) without disconnecting field wiring harnesses. The assembly attaches to standard DIN rail or surface mounting structures.

Technical Specifications

Installation Guidelines

Insert the module into the terminal base unit after setting the base keyswitch to position 2. Connect individual input wires directly to the designated terminals corresponding to channels 0 through 15 on the terminal base. Ensure external surge suppression devices are installed on field inductive lines to limit voltage spikes during power switching events.

Frequently Asked Questions

Q: What key position should be set on the terminal base for the 1794-IC16 module? A: The terminal base keyswitch must be turned to position 2 to match the mechanical keying of the 1794-IC16 module before insertion.

Q: Which terminal bases support wiring for the 1794-IC16 module? A: The module is compatible with 3-wire spring-clamp terminal base units, including the 1794-TB3S and 1794-TB3SK bases.