OM-356 Page 15
6 Minutes Welding 4 Minutes Resting
4 Minutes Welding 6 Minutes Resting
4-4. Duty Cycle And Overheating
Duty Cycle is the percentage of 10
minutes that the unit can weld at
rated load without overheating.
If unit overheats, output stops, front
panel voltmeter/ammeter displays
a HLP3 or HLP5 message (see
Section 6-4), and cooling fans run.
Wait fifteen minutes for unit to cool.
Reduce amperage or duty cycle be-
fore welding.
Y Exceeding duty cycle can
damage unit and void war-
ranty.
40% Duty Cycle At 350 Amperes (60 Hz Models Only)
Overheating
0
15
A
OR
Reduce Duty Cycle
Minutes
duty1 4/95 / SB-190 276
60% Duty Cycle At 300 Amperes
ssb1.1 10/91 − ST-190 277 / ST-190 278
The volt-ampere curves show the
minimum and maximum voltage
and amperage output capabilities of
the welding power source. Curves
of other settings fall between the
curves shown.