Hitachi RPI-0.8FSG1 Service Manual page 122

TROUBLESHOOTING
(2) Checking Procedures Transistor Module (In Case of 5 to 20HP)
Outer Appearance and Internal Circuit of Transistor Module
[Case 1]
B P
N
U
V
W
[Case 2 and 3]
N P
U
V
W
Remove all the terminals of the transistor module before check.
If items (a) to (e) are performed and the results are satisfactory, the transistor module is normal.
Measure it under 1 kΩ range of a tester. Do not use a digital tester.
(a) By touching the + side of the tester to the P terminal
of transistor module and the - side of tester to U, V
and W of transistor module, measure the resistance.
If all the resistances are from 1 to 5 kΩ, it is normal.
(b) By touching the - side of the tester to the P terminal
of transistor module and the + side of tester to U, V
and W of transistor module, measure the resistance.
If all the resistances are greater than 100 kΩ, it is
normal.
1-112
B
P
B
U
N
V
W
P
B
U
N
V
W