Lincoln Electric PRECISION TIG IM936 - Manual (Page 35)

E-4 TROUBLESHOOTING E-4
PRECISION TIG 375
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
HI-FREQ PROBLEMS
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENTS
RECOMMENDED
COURSE OF ACTION
No hi-freq
Hi-freq intensity too weak
Hi-freq on continuously in DC Tig
Hi-freq shuts off after starting in AC
Tig
1. Circuit breaker CB1 open
2. Bad connection at P12 of Control
PC board
3. Spark gaps shorted
4. Faulty Control PC board
1. Dirty spark gap or improper gap
setting
2. Faulty Arc Starter assembly
1. Bad connection at P11 of Control
PC board
2. Micro-switch S2A is not engaged &
disengaged properly when switch-
ing between DC & AC polarity.
(S2A locates on the Polarity
switch)
3. Faulty Control PC board
1. Micro-switch S2A is not engaged &
disengaged properly when switch-
ing between DC & AC polarity.
(S2A locates on the Polarity
switch)
If all recommended possible areas
of misadjustment have been
checked and the problem persists,
Contact your local Lincoln
Authorized Field Service Facility.