Mitsubishi Electric PURY-P120, Service Handbook

Page: 326 / 411

[
IX
Troubleshooting ]
- 317 - HWE09130 GB
(5) Intelligent power module (P96, P120, P144 models)
Measure resistances between each pair of terminals on the IPM with a tester, and use the results for troubleshooting.
1) Notes on measurement
Œ
Check the polarity before measuring. (On the tester, black normally indicates plus.)
Œ
Check that the resistance is not open ( ohm) or not shorted (to 0 ohm).
Œ
The values are for reference, and the margin of errors is allowed.
Œ
The result that is more than double or half of the result that is measured at the same measurement point is not allowed.
2) Tester restriction
Œ
Use the tester whose internal electrical power source is 1.5V or greater
Œ
Use the dry-battery-powered tester.
(The accurate diode-specific resistance cannot be measured with the button-battery-powered card tester, as the applied volt-
age is low.)
Œ
Use a low-range tester if possible. A more accurate resistance can be measured.
Judgment value (reference)
Black ( + )
P N U V W
Red (-)
P - - 5 - 200 ohm 5 - 200 ohm 5 - 200 ohm
N - -
U 5 - 200 ohm - - -
V 5 - 200 ohm - - -
W 5 - 200 ohm - - -
External view Internal circuit diagram
1 4 7 10 16
W
V U
B
P
N
V
U
P
W
N
B
3
2
1
6
5
4
9
8
7
11
13
10
14
15
12
16
Drive circuit
Drive circuit
Drive circuit
Drive circuit
Drive circuit
Drive circuit
Overheating -protection
circuit
Temperature
sensor
[TJMU-A]