Mitsubishi Electronics PUHY-P312 Air Conditioner User Manual


 
[ IX Troubleshooting ]
- 249 -
HWE08040 GB
(4) Simple checking procedure for individual components of main inverter circuit
Before checking, turn the power off and remove the parts to be checked from the control box.
Part name Judgment method
Diode stack Refer to "Diode stack" ( 9 [2] - 6 - (6) )
IPM (Intelligent
power module)
Refer to "Intelligent power module (IPM)" ( 9 [2] - 6 - (5) )
Rush current
protection resis-
tor
R1(R2)
<P72 and P96 models>
Measure the resistance between terminals: 22 ohm 10%
<P120 model>
Measure the resistance between the + terminal on the diode stack and terminal TB31. (*Can be mea-
sured without the need to remove the noise filter board): 22 ohm 10%
Electromagnetic
relay
72C
This electromagnetic relay is rated at 200VAC and is driven by a coil. The resistance between the
coils in row A cannot be measured with a tester.Check only for shorting.
DC reactor DCL Measure the resistance between terminals: 1ohm or lower (almost 0 ohm)
Measure the resistance between terminals and the chassis:
Current sensor
ACCT
<P120 model>
Disconnect the CNCT2 connector and measure the resistance between terminals: 280 ohm 30 ohm
1 - 2 PIN (U-phase),3 - 4 PIN (W-phase)
Check point
Row A
Not to be short-circuited
Row B to Row E
Installation direction
Test button
Row
A
Row
B
Row
C
Row
D
Row
E
A2 44 34 24 14
43 33 23 13 A1
<P72 - P96 models>
Coil
Contact
Check point
Not to be short-circuited
<P120 model>
Coil
Contact
Checking criteria
Checking criteria
Between No. 1 pin and
No. 3 pin of the CN03 on
the noise filter board
+ terminal on the diode
stack and terminal
TB31 on the noise filter
With the test button
turned off :
With the test button
turned on : 0
With the test button
turned on : 0
With the test button
turned off :
U
U
V
IPM
*Check the ACCT connection phase and the
direction of the connection
W
ACCT-W
W
ACCT-U
[THMU-A]