How To Use Troubleshooting Guide; How To Use Troubleshooting Guide - Lincoln Electric SQUARE WAVE TIG 255 SVM100-A Service Manual

F-1

HOW TO USE TROUBLESHOOTING GUIDE

Service and Repair should only be performed by Lincoln Electric Factory Trained Personnel.
Unauthorized repairs performed on this equipment may result in danger to the technician and
machine operator and will invalidate your factory warranty. For your safety and to avoid
Electrical Shock, please observe all safety notes and precautions detailed throughout this
manual.
__________________________________________________________________________
This Troubleshooting Guide is provided to
help you locate and repair possible machine
malfunctions. Simply follow the three-step
procedure listed below.
Step 1. LOCATE PROBLEM (SYMPTOM).
Look under the column labeled "PROBLEM
(SYMPTOMS)". This column describes
possible symptoms that the machine may
exhibit. Find the listing that best describes
the symptom that the machine is exhibiting.
Symptoms are grouped into three main cat-
egories: output problems, function prob-
lems, welding problems.
Step 2. PERFORM EXTERNAL TESTS.
The second column labeled "POSSIBLE
AREAS OF MISADJUSTMENT(S)" lists the
obvious external possibilities that may con-
tribute to the machine symptom. Perform
these tests/checks in the order listed. In
general, these tests can be conducted with-
out removing the case wrap-around cover.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric Service Department for technical
troubleshooting assistance before you proceed call 216-383-2531 or 1-800-833-9353.
_____________________________________________________________________
If machine case sides and top are removed the case back and front must be sup-
ported. Failure to do this could result in mechanical or electrical damage to the
TIG 255. This is best accomplished with a wooden block. Refer to Figure F.3 as
an example.
_____________________________________________________________________
HIGH VOLTAGE / HIGH FREQUENCY can damage test equipment.
• Perform all voltage and waveform checks with high frequency circuit OFF.
_____________________________________________________________________
SQUARE WAVE TIG 255
TROUBLESHOOTING & REPAIR
WARNING
Step 3. PERFORM COMPONENT TESTS.
The last column labeled "Recommended
Course of Action" lists the most likely com-
ponents that may have failed in your
machine. It also specifies the appropriate
test procedure to verify that the subject
component is either good or bad. If there
are a number of possible components,
check the components in the order listed to
eliminate one possibility at a time until you
locate the cause of your problem.
All of the referenced test procedures refered
to in the Troubleshooting Guide are
described in detail at the end of this chap-
ter. Refer to the Troubleshooting and Repair
Table of Contents to locate each specific
Test Procedure. All of the specified test
points, components, terminal strips, etc. can
be found on the referenced electrical wiring
diagrams and schematics. Refer to the
Electrical Diagrams Section Table of
Contents to locate the appropriate diagram.
CAUTION
CAUTION
CAUTION