Overload Protection - Lincoln Electric Pro-MIG 140 Operator's Manual

B-6
The Pro-MIG 140 is suitable for .035" aluminum wire
and .030" stainless wire. Refer to Table B.1 for recom-
mended procedure settings.
TABLE B.1
Shielding
Process Welding Wire Gas
.035 Dia(0.9mm 100% Argon A-4.5 C-8.5 D-10
4043 Aluminum
Wire
MIG DC+
.030 Dia 98% Argon/ B-6
308L Stainless 2% Oxygen
Steel Wire
NOTE:
NR - Not Recommended
CHANGING MACHINE OVER TO
FEED OTHER WIRE SIZES
The Pro-MIG 140 is shipped from the factory ready to
feed .035" (0.9 mm) diameter wire. To operate the
Pro-MIG 140 with other sizes of wire, it is necessary
to change the appropriate contact tip, diffuser, nozzle
and change the drive roll over to other sizes. Refer to
Changing the Contact Tip and Changing the Drive
Roll, in the MAINTENANCE section, for specific infor-
mation on these procedures.
WELDING WITH GMAW (MIG)
Shielding Gas
When using the GMAW process, the correct drive roll
and electrode polarity must be used. See Work Cable
Installation in INSTALLATION section for changing
the polarity.
When using the GMAW process, obtain and install a
gas regulator and hose kit. If using CO 2 a CO 2
adapter is required, sold separately.
1. For CO 2 , open the cylinder very slowly. For argon-
mixed gas, open cylinder valve slowly a fraction of
a turn. When the cylinder pressure gauge pointer
stops moving, open the valve fully.
OPERATION
Voltage/Wire Speed
22 ga 16 ga 12 ga 1/8" 3/16" 1/4"
NR NR NR
18 ga 16 ga 14 ga 12 ga 10ga
C-6.5 D-7.5 NR NR
Pro-MIG 140
2. If using a regulator with an adjustable flow meter,
close the gun trigger and adjust the flow to give 15
– 20 cubic ft per hour (CFH) (7 – 10 I/min.) [use 20
– 25 CFH (10 – 12 I/min.) when welding out of
position or in a drafty location for CO 2 ]. For argon
mixed gas, trigger to release gas pressure, and
adjust the flow to give 25 – 30 CFH (12 – 14
I/min.).
3. Keep the cylinder valve closed, except when using
the Pro-MIG 140. When finished welding:
a) Close the cylinder valve to stop gas flow.
b) Depress the gun trigger briefly to release the
pressure in the gas hose.
c) Turn off the Pro-MIG 140.
WELDING WITH FCAW (Innershield)
When using the FCAW process, the correct drive roll
and electrode polarity must be used. See Work Cable
Installation in INSTALLATION section for changing
the polarity.

OVERLOAD PROTECTION

Output Overload
The Pro-MIG 140 is equipped with a circuit breaker
and a thermostat which protects the machine from
damage if maximum output is exceeded. The circuit
breaker button will extend out when tripped. The cir-
cuit breaker must be manually reset.
Thermal Protection
The Pro-MIG 140 has a rated output duty cycle of
20%. If the duty cycle is exceeded, a thermal protector
will shut off the output until the machine cools to a
reasonable operating temperature. This is an auto-
matic function of the Pro-MIG 140 and does not
require user intervention. The fan continues to run
during cooling.
Electronic Wire Drive Motor Protection
The Pro-MIG 140 has built-in protection for wire drive
motor overload.
B-6