Sinclair SCV-750EB Service Manual page 148

Procedure
L34
Check whether the three-phase input
power supply of the driver board is out of
phase or wrong while Standby
No
Check whether the rear end of the L1L2
relay input is out of phase while standby
No
After power off and complete discharge,
use a multimeter to measure whether the
IPM bridge stack is damaged
No
Check whether the voltage deviation of the
driver board L1L2L3 to N is large while
standby
No
There is a deviation in the phase angle of
the three-phase power supply
6.9 L45: Abnormal current sampling circuit bias
Description
The current sampling circuit calibration has failed.

After this fault occurs, the compressor cannot be started. It is necessary to check whether there is a problem with the drive

board.
Trigger/resume condition
Trigger condition: The AD offset value of the current sampling circuit reaches half of the AD full scale.

Resume condition: After this fault occurs, the compressor cannot be started. It is necessary to check whether there is a

problem with the drive board. After that, the AD bias value of the current sampling circuit is less than half of the AD full
scale when the power is turned on again. Then this fault will not occur again.
Reset method: Automatic recovery after reaching the fault exit condition one minute later.

Possible causes
There is a problem with sampling circuit of the driver board.

Procedure
Change the driver board.

6.10 Motor code not match
Description
Parameters do not match.

 After this fault occurs, the compressor cannot be started. It is necessary to check whether there is a problem with the drive
board.
Trigger/resume condition
Trigger condition: The compressor model selected by the master through communication does not match the compressor

drive parameters in the drive.
Resume condition: Check whether the dial code of the model is wrongly dialed, and re-select the dial code of the

corresponding model.
Reset method: Re-select the dial code of the corresponding model, then power off and restart.

146
Yes
Rectify the power supply
L1L2 main relay of driver
Yes
board is not operating
Yes
Change the drive board
The power supply is not
Yes
balanced
Yes
Rectify the power supply
Change the drive board
Rectify the power supply