1756-OF8IH Allen-Bradley ControlLogix Analog Isolated Output HART 8-Point

The Allen-Bradley ControlLogix 1756-OF8IH is a ControlLogix HART I/O module featuring 15-bit resolution across 24 milliamperes. It includes 8 isolated differential outputs and a HART modem for each channel, providing robust and precise control in industrial applications.

Information About 1756-OF8IH

The Allen-Bradley 1756-OF8IH ControlLogix HART Output Module features 8 isolated differential current outputs and a HART modem per channel, fitting into any 1756 I/O chassis slot. It operates within an output range of 0-20mA and 4-20mA with 15-bit channel resolution across 24mA, drawing approximately 400mA backplane current at 24V DC. The module includes open circuit detection, ±24V DC over-voltage protection, and electronic current limiting for output short-circuit protection to 21mA or less.

Technical Specifications

BrandAllen-Bradley

CategoryPLCs/Machine Control

Part Number1756-OF8IH

SubcategoryPLC Module/Rack

ManufacturerRockwell Automation

SeriesControlLogix

Module TypeControlLogix HART I/O Module

Channels8 Isolated Differential Outputs and 1 HART Modem Per Channel

Input Current Range0-20 Miliamperes, 4-20 Miliamperes

Overvoltage Protection+/- 24 Volts DC

Resolution15 Bits Across 24 Miliamperes

Module HART Scan Time1 s w/ HART Enabled (Estimate)

Enclosure TypeNone (Open-Style)

It has a drive capability of 50-750Ω (with short circuit survival), a load reactance of 10μH, and load-dependent settling times of less than 100ms with HART enabled and less than 23ms with HART disabled. Calibration accuracy is 0.15% at 4-20mA, with a recommended calibration interval of 12 months. The module has an OFFSET drift of ±3 ppm full-scale, a GAIN drift of ±4 ppm, and a module error of 0.3% at 4-20mA.