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MAINTENANCE

SAFETY PRECAUTIONS

WARNING

Only Qualified personnel should perform this maintenance.

Turn the input power OFF at the disconnect switch or fuse box before working on this equipment.

Do not touch electrically hot parts.

INPUT POWER FACTOR

CAPACITOR DISCHARGE

PROCEDURE

This procedure ensures that the power factor capaci- tors are discharged, for greater safety when you are working on the Square Wave TIG 355 with INPUT POWER REMOVED.

1.Remove input power to the machine.

2.With a 5/16" nut driver, remove the sheet metal screws that hold the right case side in place. Remove the right case side.

3.With a volt/ohmmeter, carefully check the voltage across the input power factor capacitors. When input power is removed, the voltage across each capacitor should be zero. (Normally, the capaci- tors discharge through the primary winding in the main transformer.)

4.If capacitor voltage is zero, you may begin working on the Square Wave TIG 355.

SQUARE WAVE TIG 355

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Lincoln Electric IM467-B manual Maintenance, Input Power Factor Capacitor Discharge Procedure