Lincoln Electric SQUARE WAVE TIG 255 SVM100-A Manual Do Utilizador

Observe Safety Guidelines
detailed in the beginning of this manual.

Machine has low output when in
TIG 4-Step Mode.

Weak high frequency - machine
has normal welding output.

The display shows zero amps, but
indicates open circuit voltage
(approximately 53V).  The arc start
switch or amptrol is not actuated.

1.

Machine must be in “Local” 
Control Mode when 4-Step is 
used.

1.

Spark gap may be misadjusted.
Check and reset per 
maintenance instructions.

2.

Improper shielding gas flow.  
Adjust for a flow of 10 to 30 
CFH (4.7 to 14.1 l/min.) for 
most applications.

3.

Work and electrode cables in 
poor condition allowing high 
frequency to “Leak Off”.  Use 
good quality cables with a high 
natural rubber content,  such 
as Lincoln Stable Arc Cable.  
Cables should be as short as 
possible.

1.

The arc start switch or amptrol 
may be defective.  There should
not be any continuity between 
pins “D” and “E” on the arc start
cable connector, unless the 
unit is actuated.

2.

If an amptrol is not being used, 
the machine must be in the 
Local Control Mode.

Machine controls may be set incor-
rectly.

Contact The Lincoln Electric
Service Department (216) 383-
2531 or 1-800-833-9353 (WELD).

1.

Check for an open or arcing
high frequency component.
Replace as required.
(Examples. R3, R4, C2.) Refer
to wiring diagram.

2.

If spark is weak at the spark
gap check or replace high fre-
quency circuit. ( Examples. T3,
C3, L3, L4.)

1.

2.

Control board may be faulty.
Replace.

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.