Snap-on Tools Corporation Kenosha, WI 53141-1410
9
PROCESS SELECTION
The following controls are lo-
cated on the front of the MM140SL.
F. "ON" INDICATOR LIGHT
Illuminates when the circuit
breaker on the machine is "ON".
G. (-)NEGATIVE TERMINAL
Negative output terminal. The
work cable is plugged into this
terminal during standard weld-
ing operation. The Power plug
can be inserted into this termi-
nal for straight polarity weld-
ing on very light sheet metal, or
for using flux cored gasless
wire.
H. OCV/GAS PURGE
Operates the gas solenoid to
purge the lines of impurities
prior to welding. Pressing the
switch also causes open circuit
voltage to be registered on the
power source voltmeter.
CAUTION
Torch is electrically HOT
when switch is actuated.
I. SPOT/STITCH TIME
After the torch trigger is actu-
ated, the timer allows the wire
to feed and the gas and power to
flow for the time selected. The
Mode Switch must be set in "SPOT
or STITCH" position for timing
operation.
J. MODE SWITCH
Controls mode of operation of
welding machine. "CONT." posi-
tion is for normal, continuous
welding operation. "SPOT" posi-
tion puts the spot timer in the
circuit for automatic MIG Con-
sumable Spot Welding. "STITCH"
position is used for stitch
welding on very light materials.
K. WIRE SPEED
Potentiometer controls speed of
wire drive motor to give wire
speed of 50 to 800 inches per
minute.
A.
GAS-
CURRENT
TERMINAL
B.
CONTROL
RECEP-
TACLE
(INPUT)
C.
MIG/TIG
VOLTAGE
SWITCH
D.
VOLT-
METER
E.
CIRCUIT
BREAKER
F.
"ON"
INDICATOR
LIGHT
G.
(-)NEGATIVE
TERMINAL
H.
OCV/GAS
PURGE
I.
SPOT/
STITCH
TIME
J.
MODE
SWITCH
K.
WIRE
SPEED
L.
TORCH
PANEL
MOUNT
M.
CONTROL
RECEP-
TACLE
(OUTPUT)
N.
(+)POSITIVE
TERMINAL
A. GAS-CURRENT TERMINAL
Single terminal connection for
gas and current from welding
machine.
B. CONTROL RECEPTACLE (INPUT)
Input receptacle for wire feed
voltage, trigger circuit and
wire speed control from welding
machine.
C. MIG/TIG VOLTAGE SWITCH
Twelve position switch provides
"4" TIG (requires optional FLEX
TIG) and "8" MIG voltage set-
tings.
D. VOLTMETER
Indicates open circuit voltage
when torch trigger switch is
activated and arc (welding)
voltage during welding.
E. CIRCUIT BREAKER
Primary power switch and over-
load protection device.
(continued on following page)
FIGURE 11. FRONT PANEL
