Kaisai 06RY1, Service Manual

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The specific error codes can also be obtained from the LED indicators LED1/LED2 on the inverter module.
Table 4-4.5: Errors indicated on LED for three-phase 12~16kW unit
LED1/2 flashing pattern Corresponding error
Flashes 8 times and stops for 1 second, then repeats L0 - Inverter module protection
Flashes 9 times and stops for 1 second, then repeats L1 - DC bus low voltage protection
Flashes 10 times and stops for 1 second, then repeats L2 - DC bus high voltage protection
Flashes 12 times and stops for 1 second, then repeats
L4 - MCE error(DC bus low or high voltage protection or software over current
protection)
Flashes 13 times and stops for 1 second, then repeats L5 - Zero speed protection
Flashes 17 times and stops for 1 second, then repeats
L8 - Compressor frequency variation greater than 15Hz within one second protection
L9 - Actual compressor frequency differs from target frequency by more than 15Hz
protection
Flashes 3 times and stops for 1 second, then repeats bH - Contactor stuck or 908 self checking fail
Flashes 5 times and stops for 1 second, then repeats P1 - High pressure protection
Figure 4-4.5: LED location of inveter module for three-phase 12~16kW unit
Principle of DC inverter 4.21.5
① 380-415V AC power supply change to DC power supply after bridge rectifier.
② Contactor is open the current across the PTC to charge capacitor, after 5 seconds the contactor closed.
③ The capacitor output steady 540V DC power supply for inverter module P N terminals.
Power
supply
(380V AC)
A
B
C
Bridge
rectifier
PTC
Contactor
Inductor
Capacitor
Inverter module
(V
P-N
: 540V DC)
U
V
W
Compressor
P
N
○
3
○
1
○
2
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L0 troubleshooting 4.21.6
Situation 1: L0 error appears immediately after the outdoor unit is powered-on
L0
Communication wire between refrigerant
system main control board for refrigerant
systemnd inverter module (4 pins) not
connected properly
1
Yes
Ensure communication wire is connected
properly
No
Inverter module is damaged
2
Yes
No
Voltage between pins F0 and GND of
communication port for connection to
inverter module on the refrigerant
system main PCB is too low
3
Yes
Replace the inverter module
4
Notes:
1. For MHC-V12(14,16)W/D2RN8-B, the communication port between refrigerant system main control board for refrigerant system inverter module is port
CN36 on refrigerant system main control board for refrigerant system port CN8 on inverter module.
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.
3. The normal voltage between F0 and GND is 5V. Refer to Figure 4-4.6.
4. 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.
Figure 4-4.6: F0 and GND voltage on IC28-1
（
F0
），
IC28-4
（
GND
）
Vnormal = 5V
IC28-1
（
F0
）
IC28-4
（
GND
）
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