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Section 2 • Operational Descriptions
Blower Package PLC Operation Manual •Vilter/Emerson • 35391BLP
BLOWER
CONTROL
TARGET
0
100
DISCHARGE
RECYCLE
SETTING
DISCHARGE
PRESSURE
DISCHARGE
RECYCLE VALVE
POSITION (% OPEN)
Figure 2-6. Operational Diagram - Discharge Recycle Valve
DISCHARGE RECYCLE VALVE
If installed, the discharge recycle valve is a motorized
or air actuated valve that recycles discharge gas back to
the suction of the blower package. The valve acts as a
regulator, opening to maintain the set pressure in the
discharge line.
A PID controller adjusts the opening degree of the valve
to maintain a desired pressure on the high pressure side
of the valve. When the recycle control pressure exceeds
the desired pressure plus a deadband, the valve will start
to open to recycle high pressure gas back to suction.
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