Mitsubishi Electric FDC100VNA, Техническое руководство

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'11 • PAC-T-160
(6) Power transistor module (including the driver PCB) inspection procedure
Compressor operation
Replace the outdoor
unit inverter PCB
Normal
YES
YES
YES
NO
NO
NO
Is the power
transistor module
cracked or burnt?
Is there a
short circuit between the
power transistor module
terminals? 1
If there is a 10% or greater difference
in the current in different phases.
(except during acceleration or deceleration)
Is there any difference in
the compressor current
between phases?
Note(1) In models 200 and 250, also
replace the power transistor.
*1 Power transistor module terminal short circuit check procedure
Disconnect the compressor wiring, then conduct a short circuit check.
P-U
, P-V, P-W
N-U , N-V, N-W
Check between the P-N terminals.
Bring the tester probes in contact with the following
places on each te rminal.
P: Power transistor P terminal,
N: Power transistor N terminal,
U
: End of red harness to compressor
V: End of white harness to compressor
W: End of black or blue harness to compressor
Check for a power transistor short circuit.
• When you do not have a diagnostic checker for judging if the inverter
is defective, measure between the terminals of the power transistor
parts, judge whether the power transistor is defective or not.
• Disconnect the compressor, then measure with the controller
incorporated.
Tester Normal values (
:
)
Terminal
(+ )
Terminal
(-)
Model 71
Model
100~140
Model
200, 250
P N
0 ~
(Numerical
value rises.)
Approx. 1 M
Approx.
300~400
Scores of M
N P A few of M
P U
Several M
(Numerical
value rises.)
0
Scores of M
P V Scores of M
P W Scores of M
N U
Approx. 650 k Approx. 1.2 M
Hundreds of K
N V Hundreds of K
N W Hundreds of K
U P Approx. 670 k
Approx. 1.3 M
Hundreds of K
V P Approx. 4.4 M Hundreds of K
W P Approx. 4.4 M Hundreds of K
U N Approx. 650 k
0
Scores of M
V N Approx. 4.8 M Scores of M
W N Approx. 4.9 M Scores of M
If the measured values range from 0 ~ several kW, there is a possibility that the
elements are damaged, so replace the power transistor parts.