I've been doing my welding in a detached garage, which has a 120v/20A circuit serving the garage door opener and a couple of recepticles, along with another circuit that is 15A for the lighting (the tail end of a circuit serving lighing in the nearby laundry room). I'm hitting the limits of my 120v equipment and want to advance to a 240v welder, probably arc.
Stupidly, in this relatively new construction (2018), I didn't anticipate heavier welding in the garage, and didn't have the electrician run a dedicated 240v circuit. And doubling down on stupid, I finished much of the basement recently, cutting off the easiest path to getting wire from the main panel to the garage. So I made this task harder for myself.
Staring at most of a 250' roll of 12/2 left over from wiring the basement, I thought I would just try to snake it through to the garage (the buildings are attached by a breezeway roof, which houses the wiring between the structures) and run a dedicated 240v/20A outlet just for welding. That would probably handle 98% of what I need, and for the heaviest welding, I could move whatever portable 240v welder I get down to the basement workshop, where 240/30A or even 40A are easily implemented.
But then I started thinking about other tools I might be running in the garage, in the future: Plasma cutter, compressor, metal bandsaw. Heavier sanding equipment. I now realize, if I pull anything, it probably should be at least an 8/3, maybe a 6/3, feeding a 40A or 50A sub-panel, freeing myself from the limits of the dedicated circuits.
Just wanted to confirm with those who are more electrically aware than I: For a sub-panel, I need two hots, neutral and ground for the sub panel. The ground is grounded to the main panel ground. The neutral is bonded to the main panel neutral. The hots...each to the 120v leg of the main panel on a double pole breaker. And, the sub-panel needs a separate ground wire, to it's own ground rod. Do I have that right?
Anything else to consider?
Side note: Plenty of physical and theoretical capacity in the main (200A) breaker box.
Stupidly, in this relatively new construction (2018), I didn't anticipate heavier welding in the garage, and didn't have the electrician run a dedicated 240v circuit. And doubling down on stupid, I finished much of the basement recently, cutting off the easiest path to getting wire from the main panel to the garage. So I made this task harder for myself.
Staring at most of a 250' roll of 12/2 left over from wiring the basement, I thought I would just try to snake it through to the garage (the buildings are attached by a breezeway roof, which houses the wiring between the structures) and run a dedicated 240v/20A outlet just for welding. That would probably handle 98% of what I need, and for the heaviest welding, I could move whatever portable 240v welder I get down to the basement workshop, where 240/30A or even 40A are easily implemented.
But then I started thinking about other tools I might be running in the garage, in the future: Plasma cutter, compressor, metal bandsaw. Heavier sanding equipment. I now realize, if I pull anything, it probably should be at least an 8/3, maybe a 6/3, feeding a 40A or 50A sub-panel, freeing myself from the limits of the dedicated circuits.
Just wanted to confirm with those who are more electrically aware than I: For a sub-panel, I need two hots, neutral and ground for the sub panel. The ground is grounded to the main panel ground. The neutral is bonded to the main panel neutral. The hots...each to the 120v leg of the main panel on a double pole breaker. And, the sub-panel needs a separate ground wire, to it's own ground rod. Do I have that right?
Anything else to consider?
Side note: Plenty of physical and theoretical capacity in the main (200A) breaker box.
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