Allen-Bradley 1756-OF6CI ControlLogix Analog Output Module

Configured for precise analog current loop actuation in ControlLogix chassis architectures, the Allen-Bradley 1756-OF6CI (1756-OF6CI Analog Isolated Current Output Module) provides direct physical/electrical execution. The hardware establishes multi-channel output current generation across standard 0-20 mA and 4-20 mA industrial field control loops. Each channel offers complete channel-to-channel galvanic isolation, preventing ground loop potential differences and common-mode noise propagation between independent field circuits. The module interfaces directly with the ControlLogix backplane system for bus power distribution, module status monitoring, and deterministic command execution without requiring external signal isolation barriers for individual field loops.

Hardware Specifications

ControlLogix System Architecture & Backplane Protocol Features

The module communicates over the local ControlLogix backplane bus utilizing high-velocity CIP (Common Industrial Protocol) framing. Backplane bus communication velocity guarantees low deterministic latency during field analog updates. High-density I/O routing protocols ensure synchronous cyclic data transmission to the system controller, matching configured Requested Packet Interval (RPI) rates down to sub-millisecond thresholds. Firmware flash compatibility enables online maintenance through Studio 5000 Logix Designer without physically dismounting the chassis assembly.

Frequently Asked Questions

Q: Can the 1756-OF6CI module be removed or inserted under power (RIUP)?

A: Yes, the module supports Removal and Insertion Under Power (RIUP) within ControlLogix chassis. However, external 24 VDC field loop power connected to the 20-pin Removable Terminal Block (RTB) should be de-energized prior to disconnecting the RTB connector to prevent unintended field actuator switching.

Q: Does each channel on the 1756-OF6CI require a separate loop power source?

A: Each channel features individual channel-to-channel galvanic isolation. Channels can be powered from independent external 24 VDC field supplies or shared power sources, provided channel continuous voltage differential limits are maintained within specified isolation boundaries.

Field Installation Guidelines

• Ensure backplane chassis grounding complies with IEEE 1100 standards; ground wire connection to the enclosure star ground point must maintain low impedance using copper conductors.
• Torque standard 20-pin Removable Terminal Block (RTB) wiring terminals to manufacturer specifications to maintain solid low-resistance physical contact.
• Maintain dedicated wiring separation between analog current loop cables and high-voltage AC power lines inside system wiring trunks.
• Utilize twisted-pair shielded instrumentation cables for 4-20 mA signals, grounding the cable shield at a single cabinet point to minimize electromagnetic noise pickup.