CIGWELD TRANSarc 130i, Service Manual

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Manual 0-5280 3-1 Safety and Installation
TRANSARC 170i
SECTION 3:
SAFETY AND INSTALLATION
3.01 Duty Cycle
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 10
minute duty cycle period the following example is used. Suppose a Welding Power Source is designed to operate
at a 30% duty cycle, 170 amperes at 26.8 volts. This means that it has been designed and built to provide the
rated amperage (170A) for 3.0 minutes, i.e. arc welding time, out of every 10 minute period (30% of 10 minutes
is 3.0 minutes). During the other 7.0 minutes of the 10 minute period the Welding Power Source must idle and
be allowed to cool.
A-11712
Figure 2-1: Transarc 170i Duty Cycle