Kaisai 06RY1, Service Manual

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Notes:
1. If the fan motor is running and the DC voltage between terminals P and N on inverter module declined, Relay on the main control board of outdoor unit is
open
.
2. When replacing an inverter module, a layer of thermally conductive silica gel should be painted on IPM module (on the reverse side of the inverter module
PCB). Refer to Figure 4-4.2.
Figure 4-4.4: Relay location of main PCB for refrigerant system
Single phase 4/6/8/10kW unit Single phase 12/14/16kW unit
Relay
L5/L8/L9 troubleshooting 4.20.8
L5/L8/L9
The wire is not connected properly
NO
Ensure wire is connected properly
Yes
Inverter module PCB has malfunctioned
Yes
Replace inverter module PCB
1
No
Replace the compressor
1. When replacing an inverter module, a layer of thermally conductive silica gel should be painted on IPM module (on the
reverse side of the inverter module PCB). Refer to Figure 4-4.2.
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4.21 Inverter module Troubleshooting for three-phase models
Digital display output 4.21.1
Description 4.21.2

Inverter module protection or high pressure protection.
Mono stops running.

Specific error code L0, L1, L2, L4, L5, L8 , L9 is displayed on the user interface and the refrigerant system main
PCB.
Possible causes 4.21.3

Inverter module protection.

DC bus low or high voltage protection.

MCE error(DC bus low or high voltage protection or software over current protection)

Zero speed protection.

Excessive compressor frequency variation.

Actual compressor frequency differs from target frequency.

High pressure protection.

Contactor stuck or 908 self checking fail.
Specific error codes for inverter module protection 4.21.4
Table 4-4.4: Specific error codes
Specific error code Content
L0 Inverter module protection
L1 DC bus low voltage protection
L2 DC bus high voltage protection
L4 MCE error(DC bus low or high voltage protection or software over current protection)
L5 Zero speed protection
L8 Compressor frequency variation greater than 15Hz within one second protection
L9 Actual compressor frequency differs from target frequency by more than 15Hz protection
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