Lincoln Electric IM10009 MAGNUM PRO 250_350_450_550 - Manual (Page 16)

OPERATION
ELECTRODES AND EQUIPMENT
The MAGNUM® PRO 250, 350, 450 & 550 Amp guns
and cables have been designed for use with Lincoln L-
50 and L-56, solid steel wire electrodes for the GMAW
process and Lincoln Outershield cored electrodes for
the gas-shielded FCAW process. Refer to the appro-
priate Lincoln Process and Procedure Guidelines for
the electrode used for information on recommended
electrical and visible stickouts.
MAKING A WELD
Do not attempt to use this equipment until you
have thoroughly read all operating and mainte-
nance manuals supplied with your machine. They
include important safety precautions, detailed
engine starting, operating and maintenance
instructions and parts lists.
ELECTRIC SHOCK can kill.
• Do not touch electrically live parts
such as output terminals or
internal wiring.
• Insulate yourself from the work
and ground.
• Always wear dry insulating gloves.
------------------------------------------------------------------------
FUMES AND GASES can be
dangerous.
• Keep your head out of fumes.
• Use ventilation or exhaust to
remove fumes from breathing zone.
------------------------------------------------------------------------
WELDING SPARKS can cause fire or
explosion.
• Keep flammable material away.
------------------------------------------------------------------------
ARC RAYS can burn.
• Wear eye, ear and body protection.
------------------------------------------------------------------------
Only qualified personnel should operate this
equipment.
a. Check that the welding power source is on and that
the shielding gas supply is set for the proper flow
rate.
b. Position electrode over joint. End of the electrode
should be slightly off the work.
c. Lower welding helmet. close gun trigger and begin
welding. Hold the gun so the contact tip to work dis-
tance gives the correct electrical stickout as
required for the procedure being used.
d. To stop welding, release the gun trigger and then
pull the gun away from the work after the arc goes
out. Follow wire feeder instruction manual if using a
trigger interlock circuit.
e. If the optional interlocking trigger is installed.
-With the trigger pulled in all the way, the trigger can
be slid forward into the interlock position.
-To release the interlock, squeeze the trigger and
pull back.
AVOIDING WIRE FEEDING PROBLEMS
Wire feeding problems can be avoided by observing
the following gun handling procedures:
a. Do not kink or pull cable around sharp corners.
b. Keep the electrode cable as straight as possible
when welding or loading electrode through cable.
c. Avoid wrapping excess cable around handle or front
of wire feeder especially on longer 20 and 25 ft (6.1
and 7.6 mm) length guns.
d. Do not allow dolly wheels or trucks to run over
cables.
e. Keep cable clean by following maintenance instruc-
tions.
f. Use only clean, rust-free electrode. The Lincoln
electrodes have proper surface lubrication.
g. Replace contact tip when the arc starts to become
unstable or the contact tip end is fused or deformed.
MAGNUM® PRO 250, 350, 450 & 550 AMP
WARNING
C-1 C-1