Welder Operation

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B1.3

OPERATION

B1.3

vertical and overhead welding, use a higher “Current

WARNING

When a forceful “digging” arc is required, usually for

For example: to obtain 175 amps and a forceful arc,

Range Selector” setting and lower open circuit voltage.

ELECTRIC SHOCK can kill.

set the “Current Range Selector” to the 240-160 posi-

•

Do not touch electrically live parts or

tion and the “Fine Current Adjustment” setting to get

•

electrode with skin or wet clothing.

Insulate yourself from work and

175 amps.

ground.

Some arc instability may be experienced with EXX10

FUMES & GASES can be dangerous.

electrodes when trying to operate with long arc tech-

• Keep your head out of the fumes.

niques at settings at the lower end of the open circuit

• Use ventilation or exhaust to remove

voltage range.

CAUTION

fumes from breathing zone.

WELDING SPARKS can cause fire or

DO NOT attempt to set the “Current Range Selector”

explosion.

between the five points designated on the nameplate.

• Keep flammable material away.

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These switches have a spring loaded cam which

ARC RAYS can burn.

almost eliminates the possibility of setting this switch

• Wear eye, ear, and body protection.

between the designated points.

Duty Cycle

Idler Operation

Start the engine with the “Idler” switch in the “High”

The NEMA output rating of the Classic® 300 D is 300

position. Allow it to run at high idle speed for several

amperes at 32 arc volts on a 60% duty cycle (consult

minutes to warm the engine.

See Specifications for

Specifications in this manual for alternate ratings).

operating speeds.

Duty cycle is based on a ten minute period; thus, the

welder can be loaded at rated output for six minutes

The idler is controlled by the “Idler” toggle switch on the

out of every ten minute period.

welder control panel. The switch has two positions as

Control of Welding Current

follows:

position, the idler solenoid acti-

1. In the “High”

CAUTION

vates, and the engine goes to high idle speed. The

DO NOT TURN THE “CURRENT RANGE SELEC

speed is controlled by the governor.

TOR” WHILE WELDING because the current may

2. In the “Auto”

position, the idler oper-

arc between the contacts and damage the switch.

ates as follows:

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a. When welding or drawing power for lights or tools

The “Current Range Selector” provides five overlap-

ping current ranges. The “Fine Current Adjustment”

(approximately 100-150 watts minimum) from the

adjusts the current from minimum to maximum within

receptacles, the idler solenoid activates and the

each range. Open circuit voltage is also controlled by

engine operates at high idle speed.

the “Fine Current Adjustment” permitting control of the

b. When welding ceases or the power load is turned

arc characteristics.

A high open circuit voltage setting provides the soft

off, a preset time delay of about 15 seconds

starts. This time delay cannot be adjusted.

“buttering” arc with best resistance to pop-outs pre-

c. If the welding or power load is not re-started

ferred for most welding. To get this characteristic, set

the “Current Range Selector” to the lowest setting that

before the end of the time delay, the idler solenoid

still provides the current you need and set the “Fine

deactivates and reduces the engine to low idle

Current Adjustment” near maximum. For example: to

speed.

obtain 175 amps and a soft arc, set the “Current Range

Selector” to the 190-120 position and then adjust the

“Fine Current Adjustment” for 175 amps.

Lincoln Electric SVM194-A service manual Welder Operation, See Specifications for

Models: SVM194-A

OPERATION