Refrigeration System; Inverter Compressor - GE ZIS360NR Technical Service Manual

Inverter Compressor

The new inverter compressor is not
controlled by 120 VAC output from
the main control board, as in
previous models. The compressor
is controlled by the inverter.
Warning: Disconnecting the 6-pin
connector does not disconnect
power (120 VAC) from the inverter.
The refrigerator must be unplugged
before servicing the inverter or
compressor.
Caution: Do not attempt to
direct-start the compressor.
The compressor operates on a
3-phase power supply. Applying
120 VAC to the compressor will permanently damage the unit. It is not possible to start the
compressor without an inverter.
The compressor is a reciprocating, variable speed, 4-pole type. It operates on 3-phase, 80 to 230 VAC
within a range of 57 to 104 Hz. Compressor speed is controlled by voltage frequency and pulse width
modulation. Increasing frequency from the inverter will produce an increase in compressor speed.
• Frequency of 57 Hz will produce low speed operation at 1710 rpm.
• Frequency of 70 Hz will produce medium speed at 2100 rpm.
• Frequency of 104 Hz will produce 3120 rpm.
Note: Certain voltmeters will not be able to read voltage output or frequency from the inverter.
Compressor wattages at various speeds are:
• LOW - 65 watts
• MED - 100 watts
• HIGH - 150 watts
BTU rating also varies according to operating speed.
Compressor speed is based on the temperature set-point in conjunction with the cabinet temperature.
Speeds are selected according to the following cabinet temperatures:
• 6 °F to 19.5 °F above set-point = high speed
• 3.5 °F to 5.5 °F above set-point = medium speed
• 1 °F to 3 °F above set-point = low speed
Note: The compressor will run at medium speed if the cabinet temperature is 20 °F or more above the
set-point.
The use of 3-phase power eliminates the need for the PTCR relay, capacitor, and individual start and run
windings; therefore the start, run, and common pins found on conventional compressors are not
applicable on this 3-phase model. Compressor pin functions are identical and compressor lead wire
configuration is of no importance. A resistance of 9 to 11 W should be read between any 2 of the 3 pins.
Should an open occur in the compressor winding or should one of the compressor lead wires become
open or disconnected, the inverter will stop voltage output to the compressor.

Refrigeration System

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