Miller Electric NT 450, NT 500 manual Installation, Specifications, Duty Cycle And Overheating

SECTION 4 − INSTALLATION

4-1. Specifications

	Rated	Amperage/		Amperes Input at Rated Load Output 50/60 Hz,
						Three-Phase
Model	Welding		Max OCV−DC
		Voltage Range
	Output
				230 V	380 V	400 V	440 V	460 V	575 V	KVA	KW
			78 VDC In
		5 − 500A In CC	CC Mode For
			60 Hz
		Mode
			80 VDC In CC
	450 A @ 38
			Mode For 50 Hz	57	34	33	30	29	23	22.6	21.0
450 Amp	Volts DC, 100%
			78 VDC In	*2.18	*1.11	*1.05	*.950	*1.04	*0.84	*0.87	*0.29
	Duty Cycle
		10 − 38V In CV	CV Mode For
			60 Hz
		Mode
			80 VDC In CV
			Mode For 50 Hz
*While idling

4-2. Duty Cycle And Overheating

Duty Cycle is percentage of 10 min- utes that unit can weld at rated load without overheating.

If unit overheats, thermostat(s) opens, output stops, and cooling fan runs. Wait fifteen minutes for unit to cool. Reduce amperage or duty cycle before welding.

NOTICE − Exceeding duty cycle can damage unit and void warranty.

100% Duty Cycle

Continuous Welding

Overheating	A/V
0
	15
	OR
Minutes	Reduce Duty Cycle

duty1 4/95 / 210 976-B

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