Lincoln Electric IM665 manual Pilot ARC Discussion, Electric Shock can Kill

B-5 OPERATION B-5

5° - 15° Leading Angle

Direction of Travel

10° - 20° Arc Lag

•Use a 5° - 15° leading angle in the direction of the cut.

•Finish the cut to be made and release the trigger.

•When the trigger is released, the arc will stop.

-The gas will continue to flow for 10 seconds of postflow. If the trigger is activated within this time period, the pilot arc will immediately restart.

•If the dross is difficult to remove, reduce the cutting speed. High speed dross is more difficult to remove than low speed dross.

•The right side of the cut is more square than the left as viewed along the direction of travel.

•Clean spatter and scale from the nozzle frequently.

•If the "SAFETY" LED lights at any time; check the following:

•Check the assembly of the torch consumables. If they are not properly in place, the machine will not start. Make sure that the shield cup is hand tight. Do not use pliers or over tighten.

•Check the conditions of the inside of the nozzle. If debris has collected, rub the electrode on the inside bottom of the nozzle to remove any oxide layer that may have built up. Refer to "Suggestions for Extra Utility from the PRO-CUT system".

•Check the condition of the electrode. If the end has a crater-like appearance, replace it along with the nozzle. The maximum wear depth of the elec- trode is approximately .062”. A green and erratic arc will indicate definite electrode failure and the electrode should be replaced immediately.

•Replace the nozzle when the orifice exit is eroded away or oval shaped.

•After the problem is found, or if there is nothing apparently wrong, reset the machine by turning the power switch OFF and then ON again. (It is possi- ble for electrical noise to trip the safety circuit on rare occasions. This should not be a regular occur- rence.)

WARNING

ELECTRIC SHOCK CAN KILL.

• Turn off machine at the disconnect switch on the front of the machine before tightening, cleaning or replacing

consumables.

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•If the machine does not reset or continues to trip, consult the Troubleshooting Section.

•Use the proper cutting procedures referred to in Procedure Recommendations.

PILOT ARC DISCUSSION

The PRO-CUT has a smooth, continuous pilot arc. The pilot arc is only a means of transferring the arc to the workpiece for cutting. Repeated pilot arc starts, in rapid succession, is not recommended as these starts will generally reduce consumable life. Occasionally, the pilot arc may sputter or start intermittently. This is aggravated when the consumables are worn or the air pressure is too high. Always keep in mind that the pilot arc is designed to transfer the arc to the work- piece and not for numerous starts without cutting.

When the pilot arc is started, a slight impulse will be felt in the torch handle. This occurrence is normal and is the mechanism which starts the plasma arc. This impulse can also be used to help troubleshoot a "no start" condition.

PRO-CUT 25