Kaisai KMK-60RY1, Руководство по обслуживанию

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L1/L2 troubleshooting 4.21.7
The normal DC voltage between terminals P and N on inverter module is 540V. If the voltage is lower than 300V, the unit
displays an L1 error; if the voltage is higher than 830V, the unit displays an L2 error. Refer to Figure4-4.9.
Situation 1: L1 or L2 error appears immediately after the outdoor unit is powered-on
L1 / L2
P N +15V wire on refrigerant system main
PCB is not connected properly
1
Yes
Ensure P N +15V wire is connected
properly
No
Voltage between N and +15 is abnormal
2
Yes
Check +15V circuit
3
No
DC voltage between terminal P and N is
abnormal
Yes
Check power supply, three phase bridge
rectifier
4
No
Replace the main PCB
Notes:
1. P N +15V terminal on refrigerant system main PCB. Refer to Figure4-4.9.
2. Voltage between N and +15. Refer to Figure4-4.10
Figure 4-4.9: P, N terminals voltage
V
normal
= 540V DC
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3. Check the +15V circuit according to corresponding wiring diagram. If IC4/5/6PIN12 on inverter module output voltage is not +15V means the inverter
module is failed. If voltage output of inverter module is +15V means main PCB is failed.
4. Check the bridge rectifier using one of the following two methods (refer to Figure 4-4.11):

Method 1: measure the resistance between any two of the 5 bridge rectifier terminals. If any of the resistances is close to zero, the bridge rectifier
has failed.

Method 2: dial a multimeter to the diode setting:
- Put the red probe on the DC power output negative terminal (terminal 5) and put the black probe onto each of the AC power input terminals
(terminals 1, 2 and 3) in turn. The voltage between terminal 5 and each of terminals 1, 2 and 3 should be around 0.378V. If the voltage is 0, the
bridge rectifier has failed.
- Put the red probe on the DC power output positive terminal (terminal 4), then put black probe onto each of the AC power input terminals
(terminals 1, 2 and 3) in turn. The voltage between terminal 4 and each of terminals 1, 2 and 3 should be infinite. If the voltage is 0, the bridge
rectifier has failed.
Figure 4-4.11: Bridge rectifier
Three phase AC power input
DC power output
Figure 4-4.10: P N +15V te15V
（
IC4/5/6PIN12
）；
N-
（
IC/4/5
、
6
）
PIN13
Schematic diagram
N
+15V
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