Hobart Welding Products 187 manual Duty Cycle And Overheating, Volt-Ampere Curves, Amperes, Output

4-2. Duty Cycle And Overheating

										Duty Cycle is percentage of 10
		200								minutes that unit can weld at rated
										load without overheating.
		175								If unit overheats, thermostat(s)
		130
										opens, output stops, and cooling
	Amperes	100
										fan runs. Wait fifteen minutes for
		80								unit to cool. Reduce amperage or
		60								duty cycle before welding.
										NOTICE − Exceeding duty cycle
		40								can damage unit or gun and void
	Output
										warranty.
		20
		10
		10	20	30	40	50	60	70	80	100
				Duty Cycle %
			30% duty cycle at 130 amps, 60 Hz
			20% duty cycle at 130 amps, 50 Hz
			3 Minutes Welding		7 Minutes Resting
Overheating
				0						A or V
					15					OR
				Minutes				Reduce Duty Cycle
										duty1 4/95 − 217 757-A
4-3.	Volt-Ampere Curves

	30																					The volt-ampere curves show the
																						minimum and maximum voltage
																						and amperage output capabilities of
																						the welding power source. Curves
	25											7										of other settings fall between the
																						curves shown.
												6
	20											5
												4
Voltage												3
	15											2
												1
	10
	5
	0	0	10	20	30	40	50	60	70	80	90	100	110	120	130	140	150	160	170	180	190	200
											Amperage
																						ssb1.1 10/91 − 228 183-A
OM-228 187 Page 12