Okay, I've posted here about my fancy super-duper new garage before...
I dug into the electric a little now that we've moved in and I've had time.
There are four 240V breakers in the subpanel, a 40A, two 50A, and a 60A, with nothing at all hooked to the latter.
The 40A was previously hooked to a three-phase converter and goes through all kinds of odd fused switches (four of them in total, I don't know why), but with 10ga solid wiring encased in romex and then run through conduit pipe while along the wall, but just the romex in the exposed ceiling. I suppose that it's possible that the Sharp-branded mill he was using didn't need more than this, but I still thought that 10ga was more for 30A applications than 40A. I have since unhooked the wiring from the breaker to make it safer for me to work on everything. Funny enough, there are four wires in this group, black and white were both hot, and a red was tied off, leaving bare tied into the ground bar.
One 50A is for the heat pump, but instead of the three pair of 6ga stranded wiring I expected for a hot-hot-neutral setup there was a pair of 8ga solid wires on each legs of the hot and a much thinner, bare copper wire (I think 12ga, solid, presumably normally for ground) wired to the neutral bar, all encased together in romex. From what "the rules" indicate, either the the hot wires are too small or else the breaker is too large. Additionally, I assume that if the third wire is on neutral, it should be the same gauge as the other two. This is where I could use advice- should I swap a 40A breaker in place of the 50A that's there now due to the mismatched wire choice, or should I rewire all of the way from the heat pump to the breaker? I do not yet know the electrical demands of the heat pump, but I intend to find out if that really matters.
The circuit that the other 50A breaker was attached to looked like it had been haphazardly changed at some point. There was one 6ga stranded wire on one leg of the breaker, the other leg was empty, and the wire that should have gone to the other leg was wired to the neutral bar. The bare was wired to ground. This was all in conduit pipe, running about 50' across the garage in conduit all of the way to a pair of 120V duplex outlets on the outside of the wall. I assume that at some point they decided they needed 120V instead of 240V at that location, so they modified how it was wired up and didn't change to the appropriate breaker in the subpanel. But, there was a 20A 240V breaker just sitting on top of the subpanel, like they simply forgot to change it out. I unhooked the wiring in the panel when I added a NEMA 6-50 receptacle about a foot below the subpanel and wired it with 6ga stranded for the two hot wires and 10ga stranded for the ground.
The 60A breaker wasn't wired to anything inside the box. I don't know what they were using that for. I also can't think of anything that I'd *need* 60A for either, so that one might simply be replaced, probably with a 50A or maybe with something else...
My air compressor is wired for 240V because when we cobbled it together it kept tripping 120V 20A breakers when wired for 120V. I presume that it could run at 240V 30A, and the plug I used on the compressor is convertible between NEMA 6-50 and NEMA 6-30. I'm considering pulling out all of the wire that had been used for the three-phase stuff (and there's quite a lot of it) to see if there's enough to run all of the way to the back wall outside the workshop to mount the compressor there with a 6-30 receptacle, or if there isn't, if I have to replace the wiring for the HVAC, use that wiring for the 30A circuit for the air compressor. I could then wire the two existing 6ga runs into the same breaker, planning on using only one at a time, to give me 50A service on each side of the garage, depending on if I ever get a welder, and where I'd need to use it.
Any thoughts? I know I do tend to ramble on... Sorry...
I dug into the electric a little now that we've moved in and I've had time.
There are four 240V breakers in the subpanel, a 40A, two 50A, and a 60A, with nothing at all hooked to the latter.
The 40A was previously hooked to a three-phase converter and goes through all kinds of odd fused switches (four of them in total, I don't know why), but with 10ga solid wiring encased in romex and then run through conduit pipe while along the wall, but just the romex in the exposed ceiling. I suppose that it's possible that the Sharp-branded mill he was using didn't need more than this, but I still thought that 10ga was more for 30A applications than 40A. I have since unhooked the wiring from the breaker to make it safer for me to work on everything. Funny enough, there are four wires in this group, black and white were both hot, and a red was tied off, leaving bare tied into the ground bar.
One 50A is for the heat pump, but instead of the three pair of 6ga stranded wiring I expected for a hot-hot-neutral setup there was a pair of 8ga solid wires on each legs of the hot and a much thinner, bare copper wire (I think 12ga, solid, presumably normally for ground) wired to the neutral bar, all encased together in romex. From what "the rules" indicate, either the the hot wires are too small or else the breaker is too large. Additionally, I assume that if the third wire is on neutral, it should be the same gauge as the other two. This is where I could use advice- should I swap a 40A breaker in place of the 50A that's there now due to the mismatched wire choice, or should I rewire all of the way from the heat pump to the breaker? I do not yet know the electrical demands of the heat pump, but I intend to find out if that really matters.
The circuit that the other 50A breaker was attached to looked like it had been haphazardly changed at some point. There was one 6ga stranded wire on one leg of the breaker, the other leg was empty, and the wire that should have gone to the other leg was wired to the neutral bar. The bare was wired to ground. This was all in conduit pipe, running about 50' across the garage in conduit all of the way to a pair of 120V duplex outlets on the outside of the wall. I assume that at some point they decided they needed 120V instead of 240V at that location, so they modified how it was wired up and didn't change to the appropriate breaker in the subpanel. But, there was a 20A 240V breaker just sitting on top of the subpanel, like they simply forgot to change it out. I unhooked the wiring in the panel when I added a NEMA 6-50 receptacle about a foot below the subpanel and wired it with 6ga stranded for the two hot wires and 10ga stranded for the ground.
The 60A breaker wasn't wired to anything inside the box. I don't know what they were using that for. I also can't think of anything that I'd *need* 60A for either, so that one might simply be replaced, probably with a 50A or maybe with something else...
My air compressor is wired for 240V because when we cobbled it together it kept tripping 120V 20A breakers when wired for 120V. I presume that it could run at 240V 30A, and the plug I used on the compressor is convertible between NEMA 6-50 and NEMA 6-30. I'm considering pulling out all of the wire that had been used for the three-phase stuff (and there's quite a lot of it) to see if there's enough to run all of the way to the back wall outside the workshop to mount the compressor there with a 6-30 receptacle, or if there isn't, if I have to replace the wiring for the HVAC, use that wiring for the 30A circuit for the air compressor. I could then wire the two existing 6ga runs into the same breaker, planning on using only one at a time, to give me 50A service on each side of the garage, depending on if I ever get a welder, and where I'd need to use it.
Any thoughts? I know I do tend to ramble on... Sorry...
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