March 18, 2014
Though I am not a licensed electrician, the recommendation for a 20 AMP circuit is based on the maximum draw the Lincoln 140 welder is capable of producing. This must be included in Lincoln's literature. A welder does require a great deal of amperage and without the proper load capacity, you might kick the breaker. If you are wired with a 14 gauge wire, which is normal for a 15 amp circuit, replacing the breaker will only cause the wire to become the fuse, which you do not want. That's all like a disclaimer. If you are welding small, thin, lightweight items, using only the A or B heat settings, you will not draw all 20 AMPS. If you are using the higher heat settings on the welder, you will need the 20 AMP circuit to protect your equipment, your outlet and to produce the weld you expect.
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