LG CT09F - Page 115

Part 4 Trouble Shooting
- 115 -
Copyright © 2019 - 2020 LG Electronics Inc.
All rights reserved. Only training and service purposes.
Purpose
Checking Discrete PFC
parts for fault
Items for checking
1. Checking IGBT for damage
2. Checking FRD for damage
■ How to check IGBT, FRD (Diode Mode)
1. Remove the connector from PCB.
2. Set the Multi-Tester as Diode Voltage Measurement Mode. ( )
3. Measure the voltage as shown in Fig. 1.
4. Measure the voltage as shown in Fig. 2.
5. If the measurements are significantly different from the levels shown in the figures, the IGBT, FRD is
deemed to be damaged.
Checking Discrete PFC part
Sequence of
Measurement
Measurement
Normal
Standards
Sequence of
Measurement
Measurement
Normal
Standards
1 C – E 0.3 V~0.5 V
2 C – E 0.3 V~0.5 V
< IGBT >
❈ C : Collector / E : Emitter
1 A – C 0.3 V~0.5 V
2 A – C 0.3 V~0.5 V
< FRD >
❈ A : Anode / C : Cathode
E
C
E
C
A
C
A
ڢ
ڡ
ڡ
ڢ
IGBT
IGBT
FRD
6.7 Troubleshooting Outdoor Error
CH 27/73 (PSC/PFC Fault Error)