Mitsubishi Electric F700, Instruction Manual

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292
Inspection item
6.1.4 Display of the life of the inverter parts
The self-diagnostic alarm is output when the life span of the control circuit capacitor, cooling fan, each parts of the
inrush current limit circuit is near its end. It gives an indication of replacement time .
The life alarm output can be used as a guideline for life judgement.
Refer to page 251 to perform the life check of the inverter parts.
6.1.5 Checking the inverter and converter modules
<Preparation>
(1) Disconnect the external power supply cables (R/L1, S/L2, T/L3) and motor cables (U, V, W).
(2) Prepare a tester. (Use 100
:
range.)
<Checking method>
Change the polarity of the tester alternately at the inverter terminals R/L1, S/L2, T/L3, U, V, W, P/+ and N/ , and check
for continuity.
<Module device numbers and terminals to be checked>
(Assumes the use of an analog meter.)
Parts Judgement level
Main circuit capacitor 85% of the initial capacity
Control circuit capacitor Estimated 10% life remaining
Inrush current limit circuit Estimated 10% life remaining (Power on: 100,000 times left)
Cooling fan Less than 50% of the predetermined speed
CAUTION
1. Before measurement, check that the smoothing capacitor is discharged.
2. At the time of discontinuity, due to the smoothing capacitor, the tester may not indicate
f
. At the time of continuity, the
measured value is several to several ten-of ohms depending on the module type, circuit tester type, etc. If all measured
values are almost the same, the modules are without fault.
Tester Polarity
Measured
Value
Tester Polarity
Measured
Value
Conver
te
r
module
D1
R/L1 P/ Discontinuity
D4
R/L1 N/ Continuity
P/ R/L1 Continuity N/ R/L1 Discontinuity
D2
S/L2 P/ Discontinuity
D5
S/L2 N/ Continuity
P/ S/L2 Continuity N/ S/L2 Discontinuity
D3
T/L3 P/ Discontinuity
D6
T/L3 N/ Continuity
P/ T/L3 Continuity N/ T/L3 Discontinuity
In
ve
rte
r
mo
d
u
le
TR1
U P/ Discontinuity
TR4
U N/ Continuity
P/ U Continuity N/ U Discontinuity
TR3
V P/ Discontinuity
TR6
V N/ Continuity
P/ V Continuity N/ V Discontinuity
TR5
W P/ Discontinuity
TR2
W N/ Continuity
P/ W Continuity N/ W Discontinuity
Converter module Inverter module
D1 D2 D3
D4 D5 D6
TR1 TR3 TR5
TR4 TR6 TR2
U
V
W
R/L1
S/L2
T/L3
C
P/+
N /
−