In refineries, the Allen-Bradley 1769-OF8C module is used as a key component in the CompactLogix control system for high-precision process control and actuation drives for the following applications:

1. Control valves and flow regulation

Driving control valves (e.g. feed valves, pressure relief valves), accurately controlling valve openings by outputting 4-20mA current signals, regulating oil flow, pressure and temperature.

For example, to control the flow of heating medium in the fractional distillation column to ensure that the temperature is stabilised at the process set value.

2. Variable frequency drive (VFD) control

VFDs connecting pumps and fans dynamically adjust motor speeds through analogue signals to achieve energy optimisation (e.g. reduce energy consumption of crude oil transfer pumps).

3. Safety interlock and protection

Integrated in the PID control loop, it responds in real time to sensor data (e.g. level, temperature). If overpressure or overheating is detected, the actuator is immediately adjusted to prevent safety accidents.

The module's over-current/short-circuit protection function (output impedance >1Ω) guarantees the reliability of the equipment in the harsh electrical environment of the refinery.

4. System Integration Advantages

Compatible with CompactLogix local/expansion I/O racks, supports multi-channel synchronous outputs (8-channel independent configuration), to meet the needs of multi-point control of complex units (such as catalytic cracking unit).

Fast response (step response <2.9ms) ensures real-time performance and avoids production fluctuations.