220 Volt shop outlets

[Mike Henderson]

If you were doing 20A 120V circuits, yeah, you'd just use the 12/3, unless you wanted the future-proof-ness for 30A circuit(s) (either 2 120v circuits or 1 240V circuit).

I've always wondered if there is a reason you can't run a 120V circuit and a 240V circuit off a single piece of x/3 wire, though. Have the hots go to your 240V receptacle, and one hot and the neutral go to your 120V receptacle. Same situation as exists in an electric clothes dryer, just with two separate receptacles instead of a single 4-wire receptacle. Seems like there is no danger to doing it. The "wire utilization" would be better than two separate x/2 cable runs (if you only used one circuit at a time). Maybe it's just inconvenient because you're sharing the capacity of one wire between two circuits. Still, for situations like a shop where there may be mix of 240 and 120 tools, and if only one tool gets used at a time, it seems advantageous.

I don't know if that would fly for code, but if we ignore code, you could put a 30 amp breaker in the box because that would match the 10/3. And then do as you describe and provide both 120 and 240 on the same wires, with a limit of 30 amps on any "outside" wire.

Mike

[Van - is your place in the Denham Springs area of Louisiana?]

[Art Mann]

I don't believe that using 3 conductors plus ground to supply both 120VAC and 240VAC on one circuit is prohibited by the NEC. While I haven't done it, a few people on this forum described how they had both 120 and 240 outlets in one box. Of course, if the breaker were 30A, then the 120VAC outlet would have to be rated at 30A as well. That would be pretty unusual.

[Van Huskey]

I don't believe that using 3 conductors plus ground to supply both 120VAC and 240VAC on one circuit is prohibited by the NEC. While I haven't done it, a few people on this forum described how they had both 120 and 240 outlets in one box. Of course, if the breaker were 30A, then the 120VAC outlet would have to be rated at 30A as well. That would be pretty unusual.

I agree as I didn't find anything glaring in the NEC that would prevent it, while it might present an unbalanced load on the circuit this happens all over household wiring and if the load exceeds the breaker capacity on one leg the double pole breaker will trip both legs, by design. I don't think there is an issue here as long as someone is not trying to cheat a neutral with a ground using X/2 NM which is against code. Now, I would NOT be surprised to see an inspector ding this arrangement since it is not common practice and a AHJ might have a specific or vague rule against it.

Mike, I am 30 or so miles south southeast of Denham Springs. The problem was code (many houses in rural areas predated codes) required the standard 1 ft above the 100 year flood stage and the water was 3 feet above the 100 year flood here and higher in some areas. The VAST majority of the homes were in the preferred flood zone so mortgage companies didn't require flood insurance and the areas had never flooded in recorded history. People in waterfront neighborhoods like mine who are used to minor flooding every couple of years see things differently, kinda like the people who build on cliffs overlooking the ocean in CA, we know if we live here long enough there will be a major flood, most of use are built 5-6 feet above code. I honestly hate to leave the neighborhood as 70% or so of homes in our parish had damage, there are huge piles of drywall/flooring/insulation/furniture/appliances and just peoples lives in general sitting on the sides of the road in front of almost every house, fortunately they got the main road cleaned up last week and they were hauling off the debris from the road outside my neighborhood yesterday and today. All I have to say is one 1,000 year rain event in my life is more than enough.

[Mike Henderson]

Mike, I am 30 or so miles south southeast of Denham Springs. The problem was code (many houses in rural areas predated codes) required the standard 1 ft above the 100 year flood stage and the water was 3 feet above the 100 year flood here and higher in some areas. The VAST majority of the homes were in the preferred flood zone so mortgage companies didn't require flood insurance and the areas had never flooded in recorded history. People in waterfront neighborhoods like mine who are used to minor flooding every couple of years see things differently, kinda like the people who build on cliffs overlooking the ocean in CA, we know if we live here long enough there will be a major flood, most of use are built 5-6 feet above code. I honestly hate to leave the neighborhood as 70% or so of homes in our parish had damage, there are huge piles of drywall/flooring/insulation/furniture/appliances and just peoples lives in general sitting on the sides of the road in front of almost every house, fortunately they got the main road cleaned up last week and they were hauling off the debris from the road outside my neighborhood yesterday and today. All I have to say is one 1,000 year rain event in my life is more than enough.

I'm assuming you live on the Amite River. I'm from south Louisiana and graduated from LSU. I have friends in Denham Springs and have communicated (and continue to communicate) with them about the flood and the after effects.

Mike

[Van Huskey]

I'm assuming you live on the Amite River. I'm from south Louisiana and graduated from LSU. I have friends in Denham Springs and have communicated (and continue to communicate) with them about the flood and the after effects.

Mike

Close, I live on the Amite Diversion Canal, it may have been completly unpopulated when you were here. 15-20 years ago there were almost no homes and just a few camps, today it is neighborhood after neighborhood covering the entire diversion until you get to areas where there are no roads, there is even a community you have to drive a golf cart into since the roads stop 1/2 mile or so from the houses, not to mention the houses only accessible via boat. Mike, I have been away so long I forgot you were from this area, but when I read it I immediately remembered you had gumbo and jambalaya "tutorials" on your website! As you know it is a mess down here, but all our family (actually my in-laws, I am not from here) and close friends were not impacted directly. My entire neighborhood was stuck in our homes for 5 days though during the crest. The only trouble for me was having to ride my dog in my kayak 1/2 mile twice a day to the closest ground. We did have three boats sink due to being tied to tight to their lifts, I tried to swim out to retie one of my neghbors but even with full scuba fins the current caught me half way into my front yard and I was 100 yards downstream before I could get back the 50 feet or so to where I could climb onto a front porch, we times floating debris over known distances based on lot size and estimated the current in the middle of the river was running ~42 mph, USCG boats could barely run 10mph upstream. As with many disasters of this type the ones least finacially capable of dealing with the issues are the ones hardest hit.

BTW sorry about LSU today that was the definition of heartbreaker, while I have no skin in it my brain will be saturated with the omnipresent "fire Les Miles" chants at least until next Saturday. Hopefully the Saints will win tomorrow or I'll be ready to jump off the Mississippi bridge after a couple of days.