B-3

OPERATION

B-3

 

 

 

ENGINE CONTROLS

IGNITION SWITCH

When placed in the “ON” position, this switch ener- gizes the fuel solenoid. When placed in the “OFF” posi- tion, the flow of fuel to the injection pump is stopped to shut down the engine.

“IDLER” SWITCH

The idler switch has two positions, “HIGH” and “AUTO”.

When in “HIGH” ( ) position, the engine will run continuously at high idle.

When in “AUTO” ( / ) idle position, the idler operates as follows:

a.Welding

When the electrode touches the work, the welding arc is initiated and the engine accelerates to full speed.

After welding ceases (and no auxiliary power is being drawn), the engine will return to low idle after approximately 10 to 14 seconds.

b.Auxiliary Power

With the engine running at low idle and auxiliary power for lights or tools is drawn (approximately 100-150 watts or greater) from the receptacles, the engine will accelerate to high speed. If no power is being drawn from the receptacles ( and not weld- ing) for 10-14 seconds, the idler reduces the engine speed to low idle.

ENGINE TEMPERATURE GAUGE

Displays the coolant temperature in the engine block.

ENGINE OIL PRESSURE GAUGE

Displays the oil pressure to the engine. When the engine starts running, watch for the oil pressure to build up. If no pressure shows within 30 seconds, stop the engine and consult the engine instruction manual.

BATTERY CHARGING AMMETER

Displays the current going from the charging alternator into the batteries. It is normal for charging current to be high (above 15 amps) after starting or when the batter- ies are ‘low’ on charge.

ENGINE HOUR METER

The engine hour meter records the total running time on the engine in hours. It can be used to keep a record of maintenance on the engine and or welder.

ENGINE PROTECTION SYSTEM

The engine protection system shuts down the engine under high coolant temperature or low engine oil pres- sure conditions by allowing the fuel solenoid valve to close.

WELDER CONTROLS

POLARITY SWITCH

Turn the Arc Polarity switch to electrode positive or electrode negative as required for each particular application.

CONTROL OF WELDING CURRENT

Purpose of Controls

The continuous “Current Control” is the main current adjuster. The “Job Selector” is both a fine current adjuster and the continuous Open Circuit Voltage adjuster. Open Circuit Voltage (OCV) controls the arc characteristics.

“Job Selector”

The “Job Selector” dial is divided into four colored sec- tions providing OCV ranges as follows:

Color

Title

OCV Range

White

Large Electrodes

High OCV

Black

Normal Welding

Medium OCV

Red

Overhead & Vertical

Low OCV

Grey

Special Applications

Extra-Low OCV

 

 

 

The “Job Selector” is usually set in the black range because it provides a soft “Buttering “ arc desired for most welding. Some operators prefer to set the “Job Selector” in the red range for a snappy “Digging” arc when welding vertical up or overhead.

“Current Control”

CAUTION

Do not adjust the “Current Control” while welding because this can damage the control.

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The “Current Control” dial is calibrated in amperes on three separate colored dials corresponding to the white, black and red ranges of the “Job Selector” dial. For example: when the “Job Selector” is set on the black range, the approximate welding current is indi- cated on the black scale of the “Current Control” dial.

SAE400 & SAE400 WELD’N AIR

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Lincoln Electric IM640-A manual Engine Controls, Welder Controls