Lincoln Electric INVERTEC POWER WAVE 450 SVM112-B Service Manual page 109

F-49
INPUT RECTIFIER RESISTANCE TEST (continued)
9. Check all leads connected to the input
rectifier. Check for looseness or shorted
wires.
10. Using an analog type meter, perform the
resistance test Steps A through L accord-
ing to the Table F.1.
NOTE: If terminals AC1, AC2, and AC3 of
the input rectifier are not
accessible, use terminals T1, T2,
and T3, respectively, of main con-
tactor CR1 for the resistance mea-
surements.
POS and NEG of the input rectifier
are not easily accessible, use ter-
minals POS and NEG of the recon-
nect switch for the resistance mea-
surements.
Step
(See
Note) Test for
A 1K Ohms
B 1K Ohms
C 1K Ohms
D 1K Ohms
E 1K Ohms
F 1K Ohms
G <100 Ohms
H <100 Ohms
I <100 Ohms
J <100 Ohms
K <100 Ohms
L <100 Ohms
TROUBLESHOOTING & REPAIR
easily
Similarly, if terminals
TABLE F.1 – INPUT RECTIFIER RESISTANCE VALUES
Place Place
+ Lead - Lead
on . . . on . . .
POS AC1
POS AC2
POS AC3
AC1 NEG
AC2 NEG
AC3 NEG
AC1 POS
AC2 POS
AC3 POS
NEG AC1
NEG AC2
NEG AC3
POWER WAVE 450
11. After the test is completed and the prob-
lem successfully repaired, reconnect the
negative leads to the reconnect switch.
Fasten the reconnect switch assembly
back into position on the machine.
NOTE: If input rectifier was shorted, other
components
Perform Field Effect Transistor/
Switch Board Test and check for
"leaky" or "shorted" capacitors.
12. Install the machine case sides and top.
13. Install the handle and the lift bail rubber
gasket.
If . . . Then . . .
>1K Ohms Go to step B.
<100 Ohms Tested failed.
>1K Ohms Go to step C.
<100 Ohms Tested failed.
>1K Ohms Go to step D.
<100 Ohms Tested failed.
>1K Ohms Go to step E.
<100 Ohms Tested failed.
>1K Ohms Go to step F.
<100 Ohms Tested failed.
>1K Ohms Go to step G.
<100 Ohms Tested failed.
<100 Ohms Go to step H.
>1K Ohms Test failed.
<100 Ohms Go to step I.
>1K Ohms Test failed.
<100 Ohms Go to step J.
>1K Ohms Test failed.
<100 Ohms Go to step K.
>1K Ohms Test failed.
<100 Ohms Go to step L.
>1K Ohms Test failed.
<100 Ohms Input Rectifier OK
>1K Ohms Test failed.
F-49
may be faulty.