Lincoln Electric SP-125 PLUS, Operator'S Manual

SP-125 PLUS

A-4

INSTALLATION

3. Route the cable under and around the back of the

Wire Feed Gearbox (6).

4.

For GMAW Only: 

Refer to Figure A.2. As deliv-

ered, the SP-125 Plus is wired for positive polarity.
This is the appropriate configuration for the Gas
Metal Arc Welding (GMAW) process. To complete
installation, use the provided wing nut to connect
the work cable’s terminal lug to the negative (–)
output terminal (5) located above the Wire Feed
Gearbox (6). Make sure that both wing nuts are
tight.

5.

For Innershield Only:

Refer to Figure A.4. To wire

for negative polarity, connect the short cable
attached to the connector block (1) to the negative
(–) output terminal (2) and the work cable (3) to the
positive (+) terminal (4).

FIGURE A.4

3. Insert the connector on the gun conductor cable

through the Gun Cable Access Hole (2) in the  SP-
125 Plus case front. Make sure the connector is all
the way in the metal connector block to obtain
proper gas flow. Rotate the connector so control
leads are on the underside and tighten the
Thumbscrew (8) in the connector block.

4. Connect the gun trigger control lead terminals to

the two insulated 1/4" (6,4 mm) tab connector
bushings located above the “Gun Trigger
Connection” decal in the wire feed section (4).
Either lead can go to either connector. Form the
leads so that they are as close as possible to the
inside panel.

If the gun trigger switch being used is other than
that supplied with the SP-125 Plus, the switch
must be a normally open, momentary switch. The
terminals of the switch must be insulated from the
welding circuit. Malfunction of the SP-125 Plus will
result if this switch shorts to the SP-125 Plus
welding output circuit or is common to any electri-
cal circuit other than the SP-125 Plus trigger
circuit.

GAS CONNECTION

Refer to Figure A.5

When using the GMAW process, a cylinder of shield-
ing gas, must be obtained. For more information about
selecting gas cylinders for use with the SP-125 Plus,
refer to the ACCESSORIES section.

CYLINDER may explode if dam-
aged. 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.

GUN INSTALLATION

As shipped from the factory, the SP-125 Plus gun is
ready to feed 0.023 - 0.025” (0,6 mm) wire. If 0.030”
(0,8 mm) wire is to be used install the 0.030” (0.8 mm)
contact tip. Refer to the MAINTENANCE section for
contact tip installation details.

Connecting Gun Cable to the SP-125 Plus

1. Refer to Figure A.2. Unplug the machine or turn

power switch to the off “O” position.

2. Pass the insulated terminals of the gun trigger con-

trol leads, one at a time, through the Gun Cable
and Control Lead Access Slot (2) in the case front.
The leads are to be routed under the Wire Feed
Gearbox (6) and through the Cable Hanger (7) on
the inner panel.

CAUTION

WARNING

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