Lincoln Electric PRO-CUT 40, Operator'S Manual, Page: 17 / 30

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SYMPTOM CHECK
The air begins to flow, the “OUTPUT ON” LED 1. Check the torch consumables to be sure they
lights for a brief period and then the are in tight, not dirty or greasy, and in good
“MALFUNCTION” LED begins blinking. No arc is shape. Replace the consumables if necessary.
established. 2. Check the torch consumables to see if they are
melted together or are simply touching each
other. Tighten, clean or replace as needed.
3. Check the torch cable to see if it is cut or
punctured. Replace it as needed.
4. Check electrode to pilot for a short.
5. Check the output diodes. Perform test step 3.
6. Check the SWITCH PC BOARDS. Perform
test steps 1 and 2 for BOTH SWITCH PC
BOARDS, and perform test steps 4A and 4B.
7. Check for an open circuit in the electrode
and work leads.
8. Replace the PWM CONTROL BOARD.
9. Replace the MICRO CONTROL BOARD.
The air begins to flow, the ‘OUTPUT ON” LED 1. Check the torch consumables to be sure they
lights for a brief period and then the “MALFUNCTION” are tight, not dirty or greasy, and in good shape.
LED begins blinking. There was a brief arc. Replace the consumables if necessary.
2. Replace the PWM CONTROL BOARD.
3. Replace the MICRO CONTROL BOARD.
The arc starts but sputters badly. 1. Check the torch consumables to be sure they
are tight, not dirty or greasy and in good shape.
Replace if necessary.
2. Check air supply for oil or a great deal of water.
If there is oil or a great deal of water, the air
must be filtered or the machine switched to
nitrogen or bottled air.
Poor cutting, cutting settings drift or output 1. Check front panel wiring and controls.
power is low. 2. Replace the PWM CONTROL BOARD.
3. Replace the MICRO CONTROL BOARD.
Main fuses open or Switch PC Boards appear 1. Perform test steps 1 and 2 for both Switch PC
overheated boards, and perform test step 5.
Output power is low. Machine makes squealing 1. Perform test steps 1 and 2 for both Switch
noise while under load. Machine is connected PC Boards, and perform test steps 4A and 4B.
for 208/230V or 220V.
The “THERMAL” LED is lit. The “MALFUNCTION” 1. The machine is overheated. Allow it to cool and
LED is blinking. reset. The air intakes of the machine must not
be blocked, or this will become a nuisance