Allen-Bradley 1756-OF6CI Analog Output Module

The Allen-Bradley 1756-OF6CI is a six-channel isolated analog current-output module for Rockwell Automation’s ControlLogix systems, engineered to drive standard 4–20 mA control loops with precision. Each channel delivers a constant current in the 0–21 mA range with 13-bit resolution across the full span, providing about 2.7 µA steps for accurate loop control. The outputs are independently isolated, and each channel has its own OUT, RTN, and ALT wiring options, allowing flexible loop configurations for modern process automation. Load compatibility is defined per channel, typically supporting 0–550 Ω on the RTN path or 551–1000 Ω when using ALT returns, while backplane power draw is specified around 250 mA at 5 V for the configured loads. The module communicates faults back to the controller with per-channel fault indicators and a group fault status to aid diagnostics in complex loops. Ideal for applications such as controlling valves, actuators, flow meters, and instrumentation in industrial automation, the 1756-OF6CI provides robust, isolated current output across all six channels within a single ControlLogix I/O slot.