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O
PERATION
Operator Manual
COMMON CUTTING FAULTS
•
The workpiece is not totally penetrated. Causes can be:
-
The current is too low.
-
The cut speed is too high.
-
The torch parts are worn.
-
The metal being cut is too thick.
-
The work clamp is not properly attached to the workpiece.
•
Dross forms on the bottom of the cut. Causes can be:
-
The cutting speed is too slow.
-
The torch parts are worn.
-
The metal being cut is too thick.
-
The current is too low.
DUTY CYCLE AND OVERHEATING
•
The duty cycle is the amount of time, in minutes, that a pilot or plasma arc can remain "on" within a
10-minute period when operating at 104
°
F (40
°
C).
-
At the 25-amp setting, the arc can remain on 3.5 minutes out of every 10 minutes without
causing the temperature sensors to disable the unit.
-
At 20 amps, the duty cycle is 60%, or 6 minutes out of every 10 minutes.
-
At 17 amps, the duty cycle increases to 100%.
•
If the power supply overheats, the OVER-TEMP LED will illuminate, the arc will shut off and the
cooling fan will continue to run.
•
To resume cutting, wait for the OVER-TEMP LED to extinguish (usually 15 minutes or less) and
reduce amperage or duty cycle.
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