VRU Control Panel and Instrumentation

The VRU control system coordinates valves, beds, pumps, compressors, temperature, pressure and safety signals. A useful control package gives operators a clear view of the vapor recovery process and provides defined responses to abnormal conditions.

Control functions

Function	Typical signals or actions
Vapor header	Pressure measurement, high/low pressure alarm, isolation and bypass logic.
Bed switching	Valve sequencing, cycle timing, temperature monitoring and regeneration control.
Liquid handling	Level measurement, pump start/stop, high-level trip and drain or return routing.
Compressor or vacuum	Speed or recycle control, vibration/temperature protection and shutdown permissives.
Safety monitoring	LEL, oxygen, temperature, pressure, flame protection and emergency shutdown signals as required.

Operator information

The HMI or local panel should show the active process step, equipment status, alarms, permissives, measured values and trends needed for operation. The final screen arrangement depends on the selected control platform and the customer’s automation standard.

Integration with the plant

Confirm communication protocol, remote start/stop, hardwired trips, interlocks with loading or tank systems, analyzer signals, power supply, instrument air, cable routing and the customer’s PLC or DCS interface before fabrication.

Documents supplied with the control package

• Control philosophy and sequence description
• Instrument index and I/O list
• Alarm and trip list
• Cause-and-effect or shutdown matrix
• Panel layout, wiring information and cabinet data sheet
• Factory test procedure and operating instructions