Carrier 42UQV050M Series, Service Manual, Page: 85 / 106

11-
8
-
6
. Checking Method for Each Part
MCC-5009
Soldered
surface
Heat sink IGBT side
C12 C13 C14
~ ~
~
+ –
~
1
1 2 3
(DB
0
1)
4
4
2 3
+
–
No.
1
Part name
Electrolytic capacitor
(For boost, smoothing)
Checking procedure
1. Turn OFF the power supply breaker.
2. Discharge all three capacitors completely.
3. Check that safety valve at the bottom of capacitor is not broken.
4. Check that vessel is not swollen or exploded.
5. Check that electrolytic liquid does not blow off.
6. Check that the normal charging characteristics are shown in continuity test by the
tester.
Case that product is good
Pointer swings once, and returns slowly.
When performing test once again under
another polarity, the pointer should return.
FILE NO. SVM-13035
2 Diode block
10 to 20
Ω
when the multimeter probe is
reversed
1. Turn OFF the power supply breaker.
2. Completely discharge the four electrolytic capacitors.
3. Remove the diode block from the P.C. board (which is soldered in place).
4. Use a multimeter with a pointer to test the continuity, and check that the diode
block has the proper rectification characteristics.
Resistance value
in good product
Tester rod
+
–
~
∞
2
~
3
~
2
~
3
–
4
+
1
–
84
–