Method Of Checking The Inverter's Power Transistors And Diode Modules - Daikin VRV III REYQ8PY1 Service Manual

Method of Checking the Inverter's Power Transistors and Diode Modules

9. Method of Checking the Inverter's Power
Transistors and Diode Modules
9.1 Method of Checking the Inverter's Power Transistors
and Diode Modules
Checking failures in power semiconductors mounted on inverter PC board
Check the power semiconductors mounted on the inverter PC board by the use of a multiple
tester.
<Items to be prepared>
1 Multiple tester : Prepare the analog type of multiple tester.
<Test points>
1 Turn OFF the power supply. Then, after a lapse of 10 minutes or more, make measurement
<Preparation>
1 To make measurement, disconnect all connectors and terminals.
Inverter PC board
Electronic circuit
1 Faulty compressor (ground leakage)
1 Faulty fan motor (ground leakage)
1 Entry of conductive foreign particles
1 Abnormal voltage (e.g. overvoltage, surge (thunder), or unbalanced voltage)
In order to replace the faulty inverter, be sure to check for the points aforementioned.
420
For the digital type of multiple tester, those with diode check function are
available for the checking.
of resistance.
J1
J2
J3
DM
X10A K2
J1
L1
J2
L2
L3
J3
According to the checking aforementioned, it is probed that the malfunction results from the
faulty inverter.The following section describes supposed causes of the faulty inverter.
N3 U V
P1 P3
P1 P2 P3
N3
U
W
IGBT
V W
X11A
(V2895)
Si37-701
Appendix