Tweco 250 Weldskill MIG - Manual (Page 16)

2-4 Manual No 0-5072
welDskIll 250, 350 INTRODUCTION
December , 2008
2.07 Duty Cycle
20A plug for 250
30A plug for 250
Art # A-08725_AB
WeldSkill 250 Welding Current (amps)
Art # A-08724
Duty Cycle for 350
WeldSkill 350 Welding Current (amps)
The rated duty cycle of a Welding Power Source, is a statement of the time it may be operated at its rated
welding current output without exceeding the temperature limits of the insulation of the component parts. To
explain the 0 minute duty cycle period the following example is used. Suppose a Welding Power Source is
designed to operate at a 30% duty cycle, 350 amperes at 3.5 volts. This means that it has been designed and
built to provide the rated amperage (350A) for 3 minutes, i.e. arc welding time, out of every 0 minute period
(30% of 0 minutes is 3 minutes). During the other 7 minutes of the 0 minute period the Welding Power
Source must idle and be allowed to cool. The thermal cutout will operate if the duty cycle is exceeded.