Mitsubishi Electric City Multi CMB-P1016NU-G, Service Handbook

Page: 303 / 349

- 294 -
[
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
ΠCheck the polarity before measuring. (On the tester, black normally indicates plus.)
ΠCheck that the resistance is not open ( ohm) or not shorted (to 0 ohm).
ΠThe values are for reference, and the margin of errors is allowed.
ΠThe result that is more than double or half of the result that is measured at the same measurement point is not allowed.
Tester restriction
ΠUse the tester whose internal electrical power source is 1.5V or greater
ΠUse 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.)
ΠUse 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