B-20

B-20

OPERATION

11.Hold the Arc Start switch down until an arc is established. At this point, the Arc Start Switch can be released, and the weld will continue. Press and release the Arc Start switch a second time to stop the arc. When the Afterflow timer completes the cycle, the gas and water valves close. To make another weld, repeat steps 10 and 11.

Note: Starting difficulties may often be due to not pressing the Amptrol far enough. When the Amptrol is just “cracked,” the minimum current (2 amps) is pro- duced. Pressing the Amptrol more at the start of the weld will often solve starting problems.

OVERLOAD PROTECTION

The Square Wave TIG 355 has thermostatic protection from overloads, loss of cooling, and high ambient tem- peratures. When the welder is subjected to an over- load or loss of cooling, a thermostat will open.

If the secondary thermostat opens, the effect will be the same as pushing the Stop power pushbutton: the power will go off, the pilot light and meters will go out, and the fans will stop. Pressing the Start power push- button after the thermostat cools and resets will restart the welder.

If the primary thermostat opens, the power will stay on (pilot light and meters on and fans running), but no more than 5 amps DC output current will be available. This allows the fans to cool the machine. Depending on the amount of welder overload, the thermostat should reset within five minutes with the fan motors running. When the primary thermostat cools and resets, normal output current will be available.

AUXILIARY POWER

ALL MACHINES

The Square Wave TIG 355 provides 15 amps of 115 volt AC power at a standard NEMA 5-15R receptacle, located on the lower case back of the machine. This circuit is protected from shorts and overloading by a 15 amp circuit breaker, located next to the receptacle. The auxiliary circuit is intended for running water cool- ers and small power tools, whose current draw is with- in the 15 amp rating.

CAUTION

Note that some types of equipment, especially pumps and motors, have starting currents significantly higher than their running currents. These higher starting cur- rents may cause the circuit breaker to open. If this sit- uation occurs, the user should avoid using the Square Wave TIG 355 auxiliary for that equipment.

SQUARE WAVE TIG 355

FEB97

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Lincoln Electric IM467-B manual Overload Protection, Auxiliary Power, ALL Machines