Mitsubishi Electric FR-A500L Series Instruction Manual page 48

Checking the inverter and converter modules
<Preparation>
(1) Disconnect the external power supply cables (R, S, T) <L
(2) Prepare a tester. (Use 100 range.)
<Checking method>
Change the polarity of the tester alternately at the inverter terminals R, S, T, U, V, W, P and N <L
W, + and ->, and check for continuity.
Note: 1. Before measurement, check that the smoothing capacitor is discharged.
2. 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<L > P<+>
1
D1
P<+> R<L
1
S<L > P<+>
2
D2
P<+> S<L
2
T<L > P<+>
3
D3
P<+> T<L >
3
U P<+>
TR1
P<+> U
V P<+>
TR2
P<+> V
W P<+>
TR5
P<+> W
Converter module
D1 D2 D3
R
<L >
1
S
<L >
2
T
<L >
3
D4 D5 D6
Measured
Value
Discontinuity
D4
> Continuity
Discontinuity
D5
> Continuity
Discontinuity
D6
Continuity
Discontinuity
TR4
Continuity
Discontinuity
TR6
Continuity
Discontinuity
TR2
Continuity
P<+> Inverter module
TR1 TR3
C
TR4 TR6
N
<->
, L , L
1 2
Tester Polarity Measured
Value
R<L > N<-> Continuity
1
N<-> R<L > Discontinuity
1
S<L > N<-> Continuity
2
N<-> S<L > Discontinuity
2
T<L > N<-> Continuity
3
N<-> T<L > Discontinuity
3
U N<-> Continuity
N<-> U Discontinuity
V N<-> Continuity
N<-> V Discontinuity
W N<-> Continuity
N<-> W Discontinuity
TR5
U
V
W
TR2
37
PROTECTIVE FUNCTIONS
> and motor cables (U, V, W).
3
, L , L U, V,
1 2 3,