Routine Maintenance

D-1	MAINTENANCE	D-1

SAFETY PRECAUTIONS

WARNING

ELECTRIC SHOCK can kill.

•Turn the input power OFF at the welding power source before installation or changing drive rolls and/or guides.

•Do not touch electrically live parts.

•When inching with the gun trigger, electrode and drive mechanism are "hot" to work and ground and could remain energized several seconds after the gun trigger is released.

•Do not operate with covers, panels or guards removed or open.

•Only qualified personnel should perform main- tenance work.

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•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

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 LN-25™ PRO to the constant voltage DC welding power source. The work lead of the LN-25™ PRO must be connected to the work ter- minal of the power source.

3.Connect the reference voltmeter between the brass block of the LN-25™ PRO 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 LN-25™ PRO 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 LN-25™ PRO volt- meter.

Flow Meter Validation

Tools required:

•Flow meter reference standard.

•Constant voltage DC welding power source (DC- 400, V-350, CV-400 or equivalent).

To verify the flow meter accuracy:

1.Turn power OFF.

2.Connect the LN-25™ PRO to the constant voltage DC welding power source. The work lead of the LN-25™ PRO must be connected to the work ter- minal of the power source.

3.Connect a supply of CO2 to the wire feeder. Do not exceed the maximum inlet pressure of the wire feeder.

4.Disconnect the shielding gas hose that connects to the gun bushing.

5.Connect the shielding gas hose to flow meter refer- ence standard.

6.Orient the LN-25™ PRO in a vertical position.

7.Turn power ON.

8.Adjust the flow meter on the LN-25™ PRO to 40 scfh while pressing the GAS PURGE button.

9.Measure the gas flow with the calibrated flow meter while pressing the GAS PURGE button.

10.The measured flow rate should be between 35 and 45 scfh.