Part 4 Trouble Shooting
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Purpose
Judgment of the IPM part fault of
PCB assembly.
Items for checking
1. Checking for current detection error.
1. Set the tester in DC Voltage Mode and check the Voltage.
2. Measure the voltage of phase current detection signal – Micom GND.
3. The standard of normal voltage measurement is 2.5 V ±0.2 V.
4. If the measurement is different from the standard, replace PCBA.
! Caution
: When the measurement is made in the state that the electricity is applied, check the tester
for being in the measurement mode and be careful to avoid possible short of the parts other
than the measuring part.
Apply the electricity.
Turn indoor devices off.
Measure voltage.
Replace PCBA.
Current detection
part is normal.
Checking method
Within 2.3 ~2.7V
❈
PCBA : PCB Assembly
❈
Point each PCBA
: refer to the next page
Yes
No
Compressor Phase Current Detection Circuit
6.7 Troubleshooting Outdoor Error
CH 21 (DC Peak / Comp IPM Fault)