Checking The Inverter And Converter Modules - Mitsubishi Electric FR-A700 Instruction Manual

Maintenance and inspection
8.1.5

Checking the inverter and converter modules

Disconnect the external power supply cables (R/L1, S/L2, T/L3) and motor cables (U, V, W).
Prepare a tester. (Use 100Ω range.)
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.
b
CAUTION:
Before measurement, check that the smoothing capacitor is discharged.
At the time of discontinuity, due to the smothing capacitor, the tester may not indicate
time of continuity, the measured value is several to several ten's-of ohms depending on the mod-
ule type, circuit tester type, etc. If all measured values are almost the same, the modules are
without fault.
Converter module
Converter
module
Inverter
module
Tab. 8-4: Continuity check of the modules
FR-A700 EC
Inverter module
Tester Polarity
Measured Value
R/L1 P/+ Discontinuity
D1
P/+ R/L1 Continuity
S/L2 P/+ Discontinuity
D2
P/+ S/L2 Continuity
T/L3 P/+ Discontinuity
D3
P/+ T/L3 Continuity
U P/+ Discontinuity
TR1
P/+ U Continuity
V P/+ Discontinuity
TR3
P/+ V Continuity
W P/+ Discontinuity
TR5
P/+ W Continuity
Fig. 8-3:
Module device numbers and terminals to be
checked
Tester Polarity
R/L1 N/−
D4
N/− R/L1
S/L2 N/−
D5
N/− S/L2
T/L3 N/−
D6
N/− T/L3
U N/−
TR4
N/− U
V N/−
TR6
N/− V
W N/−
TR2
N/− W
Inspection
. At the
I001305E
Measured Value
Continuity
Discontinuity
Continuity
Discontinuity
Continuity
Discontinuity
Continuity
Discontinuity
Continuity
Discontinuity
Continuity
Discontinuity
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