Welder amp draw: what a welder pulls from the wall

The amps on the front of a welder are output amps: the current through the arc. Your breaker never sees that number. It sees input amps, the current the machine pulls from the wall, and that is the figure that decides whether a circuit can feed it.

Input draw is published in the owner’s manual, tied to a rated output. Here it is for three common machines.

Machine	Input	Rated output	Published input amps
Hobart Handler 140	115 V	90 A, 20 percent	20 A
Hobart Handler 210 MVP	115 V	90 A, 20 percent	20 A
Hobart Handler 210 MVP	230 V	150 A, 30 percent	24 A
Lincoln POWER MIG 210 MP	120 V	100 A, 40 percent	15 A
Lincoln POWER MIG 210 MP	230 V	200 A, 25 percent	14.7 A

Sources, all checked 2026-09-19: the Hobart Handler 140 spec sheet, stock number 500 500 (copy hosted by Northern Tool), the Hobart Handler 210 MVP owner’s manual OM-260 274 (ManualsLib), and the Lincoln Electric POWER MIG 210 MP operator’s manual, product number K3963-1 (ManualsLib). The percentage is duty cycle, the share of ten minutes the machine can weld at that output. See duty cycle as minutes of arc.

Why 90 amps out can mean 20 amps in

Power is volts times amps, and a welder cannot put out more power than it takes in. The Handler 140’s rated arc is 90 amps at 19 volts, about 1,700 watts. Its spec sheet lists 2.5 kilowatts of input at that output. The gap is heat and conversion loss. At 115 volts, that input works out to the 20 amps Hobart publishes.

This is the electrical ceiling on 120 volt machines. A 20 amp circuit carries about 2,400 watts in total, so the arc power available from a household outlet is limited no matter what range the badge advertises. On 240 volts the same power needs half the current, which is covered in 110v vs 220v welders.

Why a published figure can look too low

Look at the last row. The Lincoln’s rated output on 230 volts is 200 amps at 24 volts, which is 4,800 watts of arc. At 230 volts, 4,800 watts is about 21 amps before any losses. The manual’s table lists 14.7.

The likely reason is that welder manuals and nameplates carry two input currents. I1max is the draw while the arc is on at maximum rated output. I1eff is the effective current averaged over the duty cycle, and at 25 percent the machine is off most of the time. The same Lincoln table recommends a 40 amp fuse or breaker on 230 volts, which tells you the momentary draw is well above 14.7.

Two lessons. Do not size anything from a single input figure without knowing which one it is. And do not compare input amps across brands unless the manuals label them the same way. Where a manual does not say which current it lists, our tables print the figure as published and say so.

Budget inverter machines show the same pattern with bigger numbers: most machines in our multiprocess welder roundup list 35 to 46 amps of maximum input on 120 volts.

What changes the draw

• The output you set. The published figure is at rated output. Welding thin sheet at lower settings draws less.
• Input voltage. A dual voltage machine draws roughly half the current on 240 volts for the same work.
• Machine type. Inverter machines (which use electronics instead of a heavy transformer) generally convert power with less loss. We print each model’s published draw and do not estimate a saving.

Eleven machines are set side by side in the welder comparison table.

What to do with the number

Input amps is the start of the circuit question, and the manual’s breaker and wire recommendation is the next step. We walk through where to find those in what size breaker a welder needs. Planning and installing the circuit is a licensed electrician’s job.