Kaisai KMK-60RY1, Service Manual

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Situation 2: L0 or L4 error appears immediately after the compressor starts up
L0 / L4
U V W wire between inverter module and
compressor is not connected properly
1
Yes
Ensure U V W wire is connected properly
No
Inverter module is damaged
2
Yes
Replace the inverter module
3
No
Compressor has malfunctioned
4
Yes
Replace the compressor
No
Replace the outdoor unit main PCB
Notes:
1. Connect the U V W wire from the inverter module to the correct compressor terminals, as indicated by the labels on the compressor.
2. Measure the resistance between each of U, V and W and each of P and N on the inverter module. All the resistances should be infinite. If any of them are
not infinite, the inverter module is damaged and should be replaced. Refer to Figure 4-2.5 to 4-2.7 in Part 4, 2.1 “Main PCBs for Refrigerant System,
Inverter Module”.
3. When replacing an inverter module, a layer of thermally conductive silica gel should be painted on the IPM module, IGBT, diode brigde rectifer (on the
reverse side of the inverter module PCB). Refer to Figure 4-4.2.
4. The normal resistances of the inverter compressor are 0.7-1.5Ω among U V W and infinite between each of U V W and ground. If any of the resistances
differ from these specifications, the compressor has malfunctioned.
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Situation 3: L0 or L4 error appears after the compressor has been running for a period of time and the compressor
speed is over 60rps
L0 / L4
Inverter module has overheated
Yes
Repaint the thermally conductie silica
gel on the IPM module, IGBT, diode,
brigde rectifer
(on the reverse side of
the inverter module PCB)
1
No
Inverter module is over-current
2
Yes
Replace the compressor
No
Replace the inverter module
3
Notes:
1. Refer to Figure 4-4.2.
2. Use clip-on ammeter to measure the compressor current, if the current is normal indicates the inverter module is failed, if the current is abnormal
indicates the compressor is failed.
3. When replacing an inverter module, a layer of thermally conductive silica gel should be painted on the PFC and IPM modules (on the reverse side of the
inverter module PCB). Refer to Figure 4-4.2.
Situation 4: L0 error appears occasionally/irregularly
L0
The outdoor unit ventilation is not good
Yes
Ensure enough space for unit ventilation
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