Kaisai 06RY1, Service Manual

Page: 95 / 114

M thermal Mono
94 200208
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Situation 2: L0 error appears immediately after the compressor starts up
L0
DC bus wire is not connected properly
1
Yes
Ensure DC bus wire is connected properly
No
Compressor has malfunctioned
2
Yes
Replace the compressor
No
Replace the main PCB
Notes:
1. The DC bus wire should run from the N terminal on the inverter module, through the current sensor (in the direction indicated by the arrow on the current
sensor), and end at the N terminal of capacitor. Refer to Figure 4-4.7.
Figure 4-4.7: DC bus wire connection
（
L1L2L3,PIN- POUT
）
L1
，
L2
，
L3 Pin
，
Pout
2. 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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202008 95
Situation 3: L0 error appears within 2 seconds of compressor start-up
L0
U V W wire between inverter module and
compressor is not connected properly
1
Yes
Ensure U V W wire is connected properly
No
Communication port for connection to
inverter module on refrigerant system
main PCB is damaged
2
Yes
Replace the main PCB
No
Replace the inverter module
3
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 voltage between each of W-, W+, V-, V+, U-, U+ and GND when the unit is in standby. The normal voltage should be 2.5V-4V and the six
voltages should be same, otherwise the communication terminal has failed. Refer to Figure4-4.8.
Figure 4-4.8: Connection port for inverter module
3. When replacing an inverter module, a layer of thermally conductive silica gel should be painted on the IPM module (on the reverse side of the inverter
module PCB). Refer to Figure 4-4.2.
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