Compressor Sequencer Control
- Stages multiple compressors on one or more common suction lines.
- Use of a common suction pressure sensor or one of the screw compressor sensors.
- One set of common control parameters on the master sequencer is used for all compressors to eliminate sensor differences and piping loss.
- Separate control parameters for compressor capacity control and compressor starts/stops
- Adjustable staging parameters for both staging up and down compressors
- Starting of next compressor inhibited until trim compressor is fully loaded or limited.
- Re-configurable lead lists allows easy addition or removal of swing compressors.
- Multiple lead lists to allow different compressor configurations to be stored and scheduled (Standard is two with more available on request)
- Ability to select maximum compressors allow to run for each lead list
- When lead lists are changed, compressors start and stop in a controlled manner to smooth out transitions.
- Starting of skipped compressors using a standby monitor timer to maintain lead list order, as those compressors become available.
- Hot standby feature reduces starting and stopping of trim compressor.
- Support for screw, rotary, and reciprocating compressors.
- Automatic interlocks between booster and high stage systems
- Setpoint and lead list scheduling:
- Four (4) programmable setpoint groups (control setpoint, deadband, low alarm, and low failure).
- Seven (7) daily schedules each with eight time slots.
- Each time slot contains a desired lead list and a desired setpoint group
- Manual override provided for schedule number, setpoint group and lead list.
- Support for control parameters being changeable by the end user between suction pressure and process temperature.
- Ability to force a compressor on in anticipation of a load
- Support for disable ling sequencer based on conditions ( i.e. All zones are satisfied) stopping all compressors