Test is okay. go to step 6, Troubleshooting & repair, Continued) – Lincoln Electric SQUARE WAVE TIG 255 SVM100-A User Manual
Page 66: Arc start trigger circuit test
SQUARE WAVE TIG 255
F-25
TROUBLESHOOTING & REPAIR
ARC START TRIGGER CIRCUIT TEST
(continued)
PROTECTION/SNUBBER
L9255
J10
J11
J12
J13
J14
J15
10J12
3J12
3J13
11J13
6.
Test the resistance from 11J13 on the
projection/ snubber board to pin “D” on
the six pin amphenol receptacle. (Lead
#311). Also check resistance from 3J13
on the projection/snubber board to pin
“E” on the six pin amphenol receptacle.
(Lead #303).
FIGURE F.9 - PROTECTION/SNUBBER BOARD TEST POINTS.
FIGURE F.10 - ARC START TRIGGER CIRCUIT.
A. If zero ohms resistance is shown
test is okay. Proceed to projection/
snubber board test.
B. If resistance of any value is shown,
check wires and connections.