ERROR
MALFUNCTION
CODE
OR PROTECTION
DC compressor inverter
module fault
DC bus low voltage protection
(from inverter module mostly
when compressor running)
DC bus high voltage protection
from DC driver
MCE fault
Zero speed protection
Phase sequence fault
Compressor frequency variation
greater than 15Hz within
1 second protection
Actual compressor frequency
differs from target frequency
by more than 15Hz protection
FAILURE CAUSE
AND CORRECTIVE ACTION
1. Check the Heat pump system pressure;
2. Check the phase resistance of compressor;
3. Check the U、V、W power line connection sequence between the
inventer board and the compressor;
4. Check the L1、L2、L3 power line connection between the inventer
board and the Filter board;
5. Check the inventer board.
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