Miller Electric Legend 301 G Owner's Manual page 39

Trouble
Lack of high frequency; difficulty in
establishing Gas Tungsten Arc Weld-
ing arc.
Wandering arc − poor control of arc
direction.
Tungsten electrode oxidizing and not
remaining bright after conclusion of
weld.
B. 60 Hz Generator Power Receptacles RC1 And RC2
Trouble
No power output at 60 Hz ac recep-
tacles RC1 or RC2.
Low power output at 60 Hz ac recep-
tacles RC1 or RC2.
High power output at 60 Hz ac recep-
tacles RC1 or RC2.
Erratic power output at 60 Hz ac
receptacles RC1 or RC2.
C. Variable Frequency Generator Power Receptacle RC3
Trouble
No generator power output at ac re-
ceptacle RC3.
Low generator power output at ac re-
ceptacle RC3.
Use proper size tungsten for welding amperage.
Reduce leakage of high frequency from torch or work cable (check grounding, remove excessive
coils from weld cables, use shorter weld cables, etc.).
Check cables and torch for cracked or deteriorated insulation or bad connections. Repair or replace
necessary parts.
Reduce gas flow rate.
Select proper size tungsten. Properly prepare tungsten.
Shield weld zone from drafts.
Increase postflow time.
Check and tighten all gas fittings.
Properly prepare tungsten.
Reset circuit breakers CB1 and/or CB3 (see Section 7-1).
Stop welding, or place Speed Control switch in Generator Lock position to run engine at 1800 rpm. 60
Hz receptacles RC1 and RC2 work only at 1800 rpm.
Check receptacle wiring and connections.
Check fuse F1 on circuit board PC7, and replace if necessary (see Section 8-6).
Have Factory Authorized Service Agent check brushes, slip rings, and circuit boards PC1, PC2, and
PC7.
Check and clean air cleaner as necessary.
Check engine electronic governor system. See engine manual.
Check engine electronic governor system. See engine manual.
Have Factory Authorized Service Agent check brushes, slip rings, and circuit boards PC1, PC2, and
PC7.
Check receptacle wiring and connections.
Check governor according to engine manual.
Reset circuit breaker CB4 (see Section 7-2).
Check receptacle RC3 for continuity and proper connections. Replace receptacle if necessary.
Check fuse F1 on circuit board PC7 and replace if necessary (see Section 8-6).
Have Factory Authorized Service Agent check brushes and slip rings, and circuit boards PC1, PC2, and
PC7.
Check fuse F1 on circuit board PC7 and replace if necessary (see Section 8-6).
Turn Engine Control switch to Run/Idle 3600/2400 RPM position.
Remedy
Remedy
Remedy
OM-4411 Page 35