Allen-Bradley 1769-IM12 CompactLogix AC Digital Input Module

Configured for high-voltage AC discrete signal monitoring in CompactLogix and MicroLogix 1500 system platforms, the Allen-Bradley 1769-IM12 (1769-IM12 AC Input Module) provides direct physical/electrical execution across 12 non-isolated input channels.

Hardware Specifications

Backplane Bus & Deterministic Network Execution

The module transfers high-voltage AC discrete field states across the 1769 Compact I/O backplane bus communication velocity framework, delivering real-time status data directly to controller image tables. Internal optical isolators decouple 200/240 V AC field inputs from low-voltage logic circuitry, ensuring robust cross-talk suppression and system firmware flash compatibility across active controller scan cycles. Onboard filtering networks dampen AC line transient spikes and contact bounce, while direct backplane bus integration maintains consistent cyclic sampling speeds. The single-group 12-channel configuration optimizes I/O density scaling on a single-slot footprint without compromising electrical isolation margins.

Frequently Asked Questions

Q: What power supply distance rating restrictions apply when installing this module on a 1769 backplane?

A: You must mount the module within 8 slot locations of the 1769 system power supply. Placing the unit beyond an 8-module distance rating causes voltage drops across the backplane power rail, resulting in module communication faults or irregular input point processing.

Q: Are individual channels on this module galvanically isolated from each other?

A: No, the 12 input points share internally connected common returns within a single isolated group. While the entire group maintains reinforced dielectric isolation from the backplane bus, individual channels share a common AC return.

Field Installation Guidelines

Mount the module on an IEC standard DIN rail using the integrated retention latches, or attach it directly to an enclosure backplate using M4 panel mounting screws. Verify that cabinet ventilation keeps the ambient operating temperature between 0 and 60 deg C.

Strip copper conductors rated for at least 90 deg C and terminate them into the 1769-RTBN18 removable terminal block. Secure solid (22 to 14 AWG) or stranded (22 to 16 AWG) wiring to the terminal screws, tightening to a torque specification of 0.68 N m (6 lb in).

Route 200/240 V AC field input lines in separate wireways away from low-voltage DC signals, communication cables, and variable frequency drive outputs. Earth the cabinet chassis to the primary ground bus to preserve isolation barriers against external high-voltage line surges.