Lincoln Electric PRECISION TIG SVM186-A Service Manual page 56

F-16
HIGH FREQUENCY CIRCUIT DISABLE PROCEDURE (continued)
LEFT SIDE OF MACHINE
PROCEDURE
1. Remove input power to the TIG 225 machine.
2. Using the 3/8" nutdriver remove the right side
panel.
3. Locate the Spark Gap Assembly at the right
side of the machine. See Figure F.1.
4. With the 5/64" Allen type wrench loosen the set
screw holding the upper electrode in place.
5. Increase the distance between the electrodes
to at least 3/8" by sliding one electrode away
from the other electrode. Secure the one elec-
trode in this position.
6. This should disable the high frequency circuit.
Visually check to make sure high frequency
sparking is NOT present before connecting
any test equipment to the TIG 225 machine.
TROUBLESHOOTING AND REPAIR
FIGURE F.1 – SPARK GAP ASSEMBLY
PRECISION TIG® 225
7. When voltage testing and scope measurements
are complete reset the spark gap electrodes to
.020" air gap. Tighten the set screw using the
5/64" Allen wrench.
F-16
.020 Spark Gap