Mitsubishi Electric City Multi PQHY-P72 Service Handbook page 303

[ IX Troubleshooting ]
(5) Intelligent power module (IPM)
Measure resistances between each pair of terminals on the IPM with a tester, and use the results for troubleshooting.
Notes on measurement
Check the polarity before measuring. (On the tester, black normally indicates plus.)
Check that the resistance is not open (
The values are for reference, and the margin of errors is allowed.
The result that is more than double or half of the result that is measured at the same measurement point is not allowed.
Tester restriction
Use the tester whose internal electrical power source is 1.5V or greater
Use the dry-battery-powered tester.
(*The accurate diode-specific resistance cannot be measured with the button-battery-powered card tester, as the ap-
plied voltage is low.)
Use a low-range tester if possible. A more accurate resistance can be measured.
Judgment value (reference)
P
N
Red (-) U
V
W
External view
1 4 7
B
P
N
W
ohm) or not shorted (to 0 ohm).
P N
- -
- -
5 - 200 ohm
5 - 200 ohm
5 - 200 ohm
Internal circuit diagram
3
10 16
2
1
6
5
4
V U
9
8
7
11
13
10
14
15
12
16
Black ( + )
U
5 - 200 ohm 5 - 200 ohm
-
-
-
Drive circuit
Drive circuit
Drive circuit
Drive circuit
Drive circuit
Drive circuit
Temperature
sensor
Overheating -protection
circuit
- 294 -
V W
5 - 200 ohm
- -
- -
- -
P
U
V
W
B
N