GE Monogram Model # Z1SS420DRJSS

[DIYDYLAN]

Does anyone know what the output voltage should be (low voltage to compressor)? YouTube video says between 2 and 5 VDC, but I am getting 12 VDC? 

[Chat_in_FL]

The inverter receives 120 VAC line-in from the power supply. The inverter converts this single-phase,

60 Hz, 120 VAC into 3-phase, 230 VAC, with frequency variations between 57 Hz and 104 Hz. This

voltage is delivered to the compressor through 3 lead wires. Each wire will carry identical voltage and

frequency. When checking inverter voltage output, connect the test-meter leads to any 2 of the 3

compressor lead wires. The same reading should be measured between any 2 of the 3 wires.

Note:

The compressor leads must be connected to measure voltage output. If the compressor wires

are not connected, or if an open occurs in one of the 3 lead wires or in the compressor, the inverter will

stop voltage output.

The inverter controls compressor speed by frequency variation and by pulse width modulation (PWM).

Changing frequency and PWM will cause an effective voltage between 80 and 230 VAC to be received at

the compressor.

•

Low speed (1710 rpm) - 57 Hz

•

Medium speed (2100 rpm) - 70 Hz

•

High Speed (3120 rpm) - 104 Hz

The inverter receives commands from the main control board.

The main control board will send a (PWM) run signal between 1.5

and 3.5 VDC effective voltage to the inverter. The signal voltage at

the inverter should be equal to the signal voltage sent by the main

control board. The inverter will select compressor speed (voltage

output) based on this signal. A signal voltage from the main

control board (J15 connector ) lower than

5 VDC indicates a

faulty main control board. The main control board will only send a

run signal to the inverter when the compressor should be on.

Note:

When measuring signal voltage (from the main control

board) at the inverter, disconnect the wire harness connector at

the inverter and measure the voltage at the connector.

The inverter will monitor compressor operation and if the

compressor fails to start or excessive current draw (4 amps

maximum) is detected, the inverter will briefly stop voltage output.

The inverter will then make 12 consecutive compressor start

attempts (once every 12 seconds). If after 12 attempts the

compressor has not started, an 8-minute count will initiate. After

the 8-minute count, the inverter will attempt to start the

compressor again. If the compressor starts, normal operation will

resume. If the compressor fails to start, this process will be repeated. Removing power to the unit will

reset the inverter count. When power is restored, the inverter will attempt to start the compressor within

8 seconds.

The inverter has a built-in circuit protection to guard against damage from a failed or shorted

compressor. However, if a failed compressor is diagnosed, order a new compressor and inverter. If the

compressor fails to start after replacement, replace the inverter.

[DIYDYLAN]

Thanks for your feedback. 

Queation: what range of VDC should or could I see coming from J15 connector when refer is calling for compressor on (warm refer). I checked and get 12 VDC. 

[DIYDYLAN]

I think this is PWM voltage and mine is currently at 12 volts DC from mother board and at pig tail that plugs into invertor. 

[Adirondack Bob]

If I remember correctly- you should measure 4-6 VDC with the connector at the inverter connected and 12 VDC with the connector unplugged.

[DIYDYLAN]

I just checked again and it seems it has 12 VDC when unplugged and  5.4 VDC when plugged in. I think I have narrowed this down to the invertor. Thank you very much.