McQuay MDS030AR Applications Manual page 5

seconds and the unloaded state time is 5 seconds, the compressor modulation is 75%. The
capacity is a time averaged summation of the loaded state and unloaded state. By varying the
loaded state time and unloaded state time, any capacity (10%-100%) can be delivered by the
compressor.
Discharge pressure
Modulation chamber
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PWM valve power off
Valve close
Fixed scroll move downwards
Two scrolls gather together
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1.2.2 Sketch Map of Installation
Resident system
Design & installation Guide For McQuay MDS Multi System
Solenoid valve
Bleed hole
Suction pressure
Discharge pressure
Modulation chamber
Unloading
PWM valve power on
Valve open
Fixed scroll moves upwards
Two scrolls separate
Unloading
Commerce system
Solenoid valve
Bleed hole
Suction pressure
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