To prevent motor overload during start-up of a hermetically sealed centrifugal refrigeration system, what is true concerning the compressor suction gas variable inlet guide vanes?

Correct Answer: Option A — closed until the motor is connected across the line at full voltage and current drawn is below full load current

Variable inlet guide vanes must remain fully closed during hermetic centrifugal compressor start-up to minimize gas throughput, reducing starting torque and preventing electrical motor overload before full-load operating speed and current stabilization occur.