Lincoln Electric IM675 RED-D-ARC E300 - Manual (Page 15)

E-2 TROUBLESHOOTING E-2
RED-D-ARC E300
Observe all Safety Guidelines detailed throughout this manual
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your
Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENTS(S)
RECOMMENDED
COURSE OF ACTION
Rectifier Troubleshooting 1. Turn the input power off.
2. Disconnect all input and output
leads from the rectifier bridge.
3. Connect an ohmmeter between
the DC positive (red) terminal
and one of the Center AC termi-
nals. Note the ohmmeter read-
ing using the 10 to 100 scale.
4. Reverse the ohmmeter leads.
Note the readings.
5. The reading taken in steps 3
and 4 should be different. If
the readings are the same and
near zero, the rectifier has
shorted. IF the readings are
the same and near full scale,
the rectifier has failed open.
6. Repeat steps 3, 4 and 5
between the DC positive (red)
terminal and each of the
Center AC terminals.
7. Repeat steps 3, 4 and 5
between the DC negative
(black) terminal and each of
the Center AC terminals.
NOTE: Since it is unlikely that all
rectifiers of a full wave bridge
would fail simultaneously, check
the test method and the ohmmeter
if the checking indicates that all
rectifiers have failed.
If all recommended possible areas of
misadjustment have been checked
and the problem persists, Contact
your local Lincoln Authorized
Field Service Facility.