Mitsubishi Electronics FR-A500L Welding System User Manual


 
PROTECTIVE FUNCTIONS
37
z
Checking the inverter and converter modules
<Preparation>
(1) Disconnect the external power supply cables (R, S, T) <L
1
, L
2
, L
3
> 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, S, T, U, V, W, P and N <L
1
, L
2
, L
3,
U, V,
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 Tester Polarity
Measured
Value
Measured
Value
R<L
1
> P<+> Discontinuity R<L
1
> N<-> Continuity
D1
P<+> R<L
1
> Continuity
D4
N<-> R<L
1
> Discontinuity
S<L
2
> P<+> Discontinuity S<L
2
> N<-> Continuity
D2
P<+> S<L
2
> Continuity
D5
N<-> S<L
2
> Discontinuity
T<L
3
> P<+> Discontinuity T<L
3
> N<-> Continuity
Converter module
D3
P<+> T<L
3
> Continuity
D6
N<-> T<L
3
> Discontinuity
U P<+> Discontinuity U N<-> Continuity
TR1
P<+> U Continuity
TR4
N<-> U Discontinuity
V P<+> Discontinuity V N<-> Continuity
TR2
P<+> V Continuity
TR6
N<-> V Discontinuity
W P<+> Discontinuity W N<-> Continuity
Inverter module
TR5
P<+> W Continuity
TR2
N<-> W Discontinuity
D1 D2 D3
D4 D5 D6
TR1 TR3 TR5
TR4 TR6 TR2
U
V
W
R
<L
1
>
S
<L
2
>
T
<L
3
>
C
P<+>
N
<->
Inverter moduleConverter module