Lincoln Electric IM-939A Routine Maintenance, Periodic Maintenance, Calibration Specification

SAFETY PRECAUTIONS

WARNING

ELECTRIC SHOCK can kill.

• Do not operate with covers removed.

•Turn off power source before installing or servicing.

•Do not touch electrically hot parts.

•Turn the input power to the welding power source off at the fuse box before working in the terminal strip.

•Only qualified personnel should install, use or service this equipment.

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ROUTINE MAINTENANCE

•Check weld cables, control cables and gas hoses for cuts.

•Clean and tighten all weld terminals.

PERIODIC MAINTENANCE

•Clean drive rolls and inner wire guide and replace if worn.

•Blow out or vacuum the inside of the feeder.

CALIBRATION SPECIFICATION

The voltmeter and flow meter are not calibrated and are for reference purposes only.

Voltmeter Validation, Across the Arc Analog Meter Models

Tools required:

•DC voltmeter reference standard

•Constant voltage DC welding power source with adjustable no-load voltage (DC-400, V-350, CV-400 or equivalent).

To verify the analog voltmeter accuracy:

1.Turn power OFF.

2.Connect the LN25 PRO EXTREME to the constant voltage DC welding power source. The work lead of the LN25 PRO EXTREME must be connected to the work terminal of the power source.

3.Connect the reference voltmeter between the brass block of the LN25 PRO EXTREME and the work lead.

4.Turn power ON.

5.Energize the output circuit of the power source. Adjust the power source output to 20±1 VDC as measured on the reference meter.

6.Verify that LN25 PRO EXTREME voltmeter reads between 19 and 21 volts.

If the voltmeter reading is out of range, check for loose connections or replace the voltmeter. There is no calibration adjustment for the LN25 PRO EXTREME voltmeter.