Mitsubishi Electric FR-S500 Instruction Manual page 60

Checking the inverter and converter module
<Preparation>
(1) Disconnect the external power supply cables (R, S, T) and motor cables (U, V, W).
(2) Prepare a tester. (Use 100Ω range).
<Checking method>
Change the polarity of the tester alternately at the inverter terminals R, S, T, U, V, W, P
and N, and check for continuity.
CAUTION
•Before measurement, check that the smoothing capacitor is discharged.
•At the time of discontinuity, the measured value is almost ∞. When there is an
instantaneous continuity, due to the smoothing capacitor, the tester may not
indicate ∞. At the time of continuity, the measured value is several to several
ten's-of ohms depending on the module type, circuit tester type, etc. If all
measured values are almost the same, the modules are without fault.
Module device numbers and terminals to be checked
Tester Polarity
R
D1
P
S
D2
P
T
D3
P
U
TR1
P
V
TR3
P
W
TR5
P
R
S
T
Process
value
P Discontinuity
R Continuity
P Discontinuity
S Continuity
P Discontinuity
T Continuity
P Discontinuity
U Continuity
P Discontinuity
V Continuity
P Discontinuity
W Continuity
Converter
P
module
D1 D2 D3
C
D4 D5 D6
N
55
Precautions for maintenance and inspection
Tester Polarity
R
D4
N
S
D5
N
T
D6
N
U
TR4
N
V
TR6
N
W
TR2
N
(Assumes the use of an analog meter.)
Inverter module
TR1 TR3 TR5
TR4 TR6 TR2
Process
value
N Continuity
R Discontinuity
N Continuity
S Discontinuity
N Continuity
T Discontinuity
N Continuity
U Discontinuity
N Continuity
V Discontinuity
N Continuity
W Discontinuity
U
V
W
7