Mitsubishi Electric City Multi PQHY-P72 Service Handbook page 302

(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
Diode stack Refer to "Diode stack" ( 9.[4].5.(6) )
IPM (Intelligent power Refer to "Intelligent power module (IPM)" ( 9.[4] -5- (5) )
module)
Rush current protection re- Measure the resistance between terminals: 22 ohm +- 10%
sistor
R1
Electromagnetic relay
52C
Electromagnetic con-
tactor
52F
DC reactor DCL Measure the resistance between terminals: 1ohm or lower (almost 0 ohm)
Measure the resistance between terminals and the chassis:
Noise filter
Current sensor ACCT Disconnect the CNCT2 connector and measure the resistance between terminals: 280 ohm +- 30 ohm
1 - 2 PIN (U-phase),3 - 4 PIN (W-phase)
Measure resistance between terminals on each row.
Installation direction
Row Row Row Row
A B C
Test button
A1
L1 L2 L3
Pushbutton
U V W
Resistance check between each terminal
and between terminal and case.
FN1
FN2
FN3
ACCT-U
* Check the ACCT connection phase and the
direction of the connection.
- 293 -
Judgment method
Check point
Row
Row A
D E
Row B to Row E
* The coil is driven when AC 208 / 230V is applied.
Note that the coil is not driven at DC 12V, which is
different from the conventional relays.
The resistance of row A cannot be measured with
a tester. Check that it is not short-circuited.
Check point
A1-A2
Button
on
A2
(hold down)
13
Button
14
OFF
Check point
FN 3 - 6 , FN 2 - 4
FN 1 - 2 , FN 2 - 3 ,
FN 4 - 6
FN4
FN1 , FN2 , FN3 ,
FN6
FN 4, FN6
U W ACCT-W
U V W
IPM
[ IX Troubleshooting ]
Judgment value
Short circuit is not allowed.
Judgment value
0.1 k ~ 2.0 k
1 or less (almost 0 )
L1 - U
L2 - V 1 or less (almost 0 )
1 or less (almost 0 )
L3 - W
13 - 14 1 or less (almost 0 )
31 - 32
L1 - U
L2 - V
L3 - W
13 - 14
1 or less (almost 0 )
31 - 32
Judgment value
1 or less (almost 0 )