Coaxial Weld Cable; Electrode Polarity; Shielding Gas Connection - Lincoln Electric POWER FEED 15M IM761 Operator's Manual

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COAXIAL WELD CABLE

Coaxial welding cables are specially designed welding
cables for pulse welding or STT welding. Coaxial weld
cables feature low inductance, allowing fast changes in the
weld current. Regular cables have a higher inductance
which may distort the pulse or STT waveshape. Inductance
becomes more severe as the weld cables become longer.
Coaxial weld cables are recommended for all pulse and STT
welding, especially when the total weld cable length (elec-
trode cable + work cable) exceeds 50 feet (7.6m)
A coaxial weld cable is constructed by 8 small leads
wrapped around one large lead. The large inner lead con-
nects to the electrode stud on the power source and the
electrode connection on the wire feeder. The small leads
combine together to form the work lead, one end attached to
the power source and the other end to the work piece. See
Figure A.5
FIGURE A.5
Electrode
Work
Power Source Power Source
W W ork ork Electrode Electrode
Coaxial Weld Cable Coaxial W eld Cable

ELECTRODE POLARITY

CAUTION
When changing the electrode polarity, the weld cables must be
changed at the power source studs and the DIP switch inside the
Power Feed 15M must be properly set. Operation with the DIP
switch in the wrong position will cause erratic arc performance.
The Power Feed 15M is factory set for Electrode Positive weld-
ing. Most welding procedures use Electrode Positive welding.
Some Innershield procedures may use Electrode Negative
welding.
To change the DIP switch iside the Power Feed 15M electrode
polarity:
1. Turn off power at the welding power source.
2. Remove the rear access panel on the wire drive.
3. Locate DIP switches on the Wire Drive Board.
4. Set DIP switch #7 to the desired polarity.
DIP Switch #7 Position Polarity
ON (Up) - (negative) polarity
OFF (Down) + (positive) polarity
5. Assemble the rear access panel to the wire drive.
6. Restore power.
INSTALLATION
Work
Electrode Electrode
Wire Feeder Wire Feeder
W W ork ork
POWER FEED 15M

SHIELDING GAS CONNECTION

WARNING
CYLINDER may explode if
damaged.
• Keep cylinder upright and
chained to support.
• Keep cylinder away from areas where it may be
damaged.
• Never lift welder with cylinder attached.
• Never allow welding electrode to touch cylinder.
• Keep cylinder away from welding or other live
electrical circuits.
• BUILD UP OF SHIELDING GAS MAY HARM
HEALTH OR KILL.
• Shut off shielding gas supply when not in use.
• See American National Standard Z-49.1, "Safety
in Welding and Cutting" Published by the
American Welding Society.
------------------------------------------------------------------------
Install the shielding gas supply as follows:
1. Secure the cylinder to prevent it from falling.
2. Remove the cylinder cap. Inspect the cylinder valves and
regulator for damaged threads, dirt, dust, oil or grease.
Remove dust and dirt with a clean cloth. DO NOT
ATTACH THE REGULATOR IF OIL, GREASE OR DAM-
AGE IS PRESENT! Inform your gas supplier of this con-
dition. Oil or grease in the presence of high pressure oxy-
gen is explosive.
3. Stand to one side away from the outlet and open the
cylinder valve for an instant. This blows away any dust or
dirt which may have accumulated in the valve outlet.
4. Attach the flow regulator to the cylinder valve and tighten
the union nut(s) securely with a wrench. Note: if connect-
ing to 100% CO2 cylinder, insert regulator adapter
between regulator and cylinder valve. If adapter is
equipped with a plastic washer, be sure it is seated for
connection to the CO2 cylinder.
5. Attach one end of the inlet hose to the outlet fitting of the
flow regulator. Attach the other end to the welding system
shielding gas inlet. Tighten the union nuts with a wrench.
6. Before opening the cylinder valve, turn the regulator
adjusting knob counterclockwise until the adjusting spring
pressure is released.
7. Standing to one side, open the cylinder valve slowly a
fraction of a turn. When the cylinder pressure gage stops
moving, open the valve fully.
8. The flow regulator is adjustable. Adjust it to the flow rate
recommended for the procedure and process being used
before making a weld.
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