TM 5-3431-225-15
normally open maintained contact switch must be
connected to the contactor control receptacle.
With this switch engaged, the contactor in the
welding machine is energized, starting gas and
water flow. Full open circuit voltage (when no
arc is established) and high frequency is present
(with the switch in either "Start" or "Contin-
uous" position) and the start adjustment control
circuit is energized. When welding is begun, the
high frequency will shut off (with the switch in
the "Start" position only), and the start adjust-
ment control will change to the main welding
control. Welding can continue as long as the re-
mote control switch is maintained in the closed
position, To stop welding, the control switch
must be opened; this drops out the contactor and
breaks the arc. The post flow gas timer will start
to time out.
Note. If the arc is broken manually, gas and
water will continue to flow, full open circuit voltage is
present, high frequency is present (if switch is in "Con-
tinuous" position) and the start adjustment control cir-
cuit is energized. The maintained contact witch must be
opened to deenergize the welding circuit.
(2) "B" panel. This type of operation is
used for manual welding. The contactor control
switch must be in the remote position. A mo-
mentary contact switch must be connected to the
contactor control receptacle. With this switch en-
gaged the contactor in the welding machine is
energized, starting gas and water flow. Full open
circuit voltage (when no arc is established) and
high frequency is present (with the switch in
either "Start" or "Continuous" position) and
c. Use a sample piece of metal, like the metal
the start adjustment circuit is energized. When
to be welded and adjust the welding amperage
welding is begun, the remote contactor control
to produce the correct arc necessary for the weld-
switch can be released, the high frequeney will
ing to be done.
shut off (with the switch in the "Start" position
Warning: Do not come in contact with the
only) and the start adjustment control will
electrode while the welding machine is operat-
change to the main welding control. To stop
ing. The high voltage generated by the machine
welding, break the arc by withdrawing the elec-
can cause death by electrocution.
trode holder from the work. The contactor will
open and gas and water will start to time out
d. The connections on the terminal blocks lo-
automatically.
cated on the relay panel on the left side of the
machine (fig. 4-10) must be properly positioned
(3) "S" panel. This type of operation is
for the type of welding to be done. These three
used for spot welding. When using the "S" panel
connections are known as Panel "A" used for
control, it will be necessary to position the "Auto-
automatic welding, Panel "B" used for manual
matic-Manual" switch as required. With the
welding, and Panel "S" used for spot welding,
"Automatic-Manual" switch in the "Manual"
Proper connections for each panel are shown in
position, "A" control operation is possible. With
the switch in the "Automatic" position, "S" con-
chine in each panel is as follows:
trol operation is possible. When using the "S"
(1) "A" panel. This type of operation is
control for gas tungsten-arc spot welding, it will
used for automatic welding. The contactor con-
be necessary to place the contactor control switch
trol switch must be in the "remote" position. A
in the "Remote" position. The weld timer, lo-
2-10
