Sinclair SCV-EB Series Service Manual page 85

5.29.6 L1/L2 troubleshooting
The normal DC voltage between terminals P and N on inverter module is 540V. If the voltage is lower than 250V, the unit
displays an L1 error; if the voltage is higher than 720V, the unit displays an L2 error.
P, N terminals voltage
Situation 1: L1 or L2 error appears immediately after the outdoor unit is powered-on
P N wire on refrigerant system PCB is not
connected properly
Voltage between N and +15 is abnormal
DC voltage between terminal P and N is
Replace the main PCB
Notes:
1. Voltage between N and +15.
V
L1 / L2
No
No
abnormal
No
= 540V DC
normal
Yes
Ensure P N wire is connected properly
Yes
2
Check power supply, three phase bridge
Yes
3
Check +15V circuit
4
rectifier
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