Fix Until Broke
Well-known member
We got a bit off track over in the "Lift Modifications - Let's See Them" thread so this thread was created to clean that one up and give a more relevant place to have this discussion.
Please feel free to continue discussions below so as to keep the lift modifications thread clean. A link to this thread will be placed over there and vice versa to cross reference.
Please feel free to continue discussions below so as to keep the lift modifications thread clean. A link to this thread will be placed over there and vice versa to cross reference.
Thank you! I’m planning to go with 6 gauge wire with 50A breaker. Hopefully it will be possible to feed it through the metal conduit with a lot of turns
Run 4 wires rated for 50A (or whatever current your breaker will be) over to the hoist.
- Black = 120v "A" phase
- Red = 120v "B" phase
- White = Neutral (can be smaller 12 gauge wire depending on length)
- Green = Ground
Wire in your 240 outlet for the welder using Red, Black and Green. Tap off each side of the 240 outlet with the same gauge wire and run to a pair of 15 or 20 amp breakers in a sub panel like shown below and then power a "quad box" with each duplex outlet fed by one of the 15 or 20 amp breakers. White is the neutral for the 120v outlets, Green is ground again. The white wire can carry the current for both 120v circuits simultaneously since they're out of phase.
Here's another option with both combined in one box. It's $80 and you probably don't need the IP65 rating, but it's clean.
https://www.asi-ez.com/member/~RAI-DAC-109-B.asp?
I think we're saying the same thing, but maybe in different ways? I'm not an electrician either (also an engineer so maybe we're the blind leading the blind
On the 240v circuit the current goes back/forth between the black and red wires - no neutral or ground necessary (recommended for safety, but not necessary for operation).
On the 120v circuits the current goes back/forth between the black and white wires on one outlet and between the red and white wires on the other outlet. Since the current on the black and red wires are out of phase, when the current is high on the black wire, it's low on the red wire so the current on the white wire is ~constant.
Any electricians able to straighten us out here?
Agreed on the 240v circuit - no neutral needed - Size the red/black wires for the full 50A to this plug.
On either of the 20A 120v circuits, if you plug a drill into one of them (Black for example), the white and black wire will carry the same current at the same time (ignoring power factor here) - Let's call it 4 amps RMS.
If you plug a halogen light into the Red circuit that draws 10 amps RMS and use the 4 amp RMS drill at the same time there will NOT be 14 amps RMS in the white wire, instead it will be 6 amps - the difference between the two loads since they're out of phase. The white wire will only carry the difference in current between the red and black wire at any point in time, not the sum of the current in the red and black wires.
Much better explained in the link below by those who know what they're doing
https://www.allaboutcircuits.com/textbook/alternating-current/chpt-10/single-phase-power-systems/
Some welders may take up to 35A and they are usually equipped with NEMA 6-50 plug. I guess it's against the code to use NEMA 6-50 outlet with 10 gauge wires and 30A breaker?
What's the best way to split the 240 for the outlet and for the hoist? I took a pic on the 6 gauge wire size and was pretty impressed. I'm not sure if the twisting nuts is an answer
I also purchased the remote little box for 2 15-20A breakers to make the double (or actually quadruple) 120 from 240.
Also do you think 1" metal conduit is enough for 6-3 wire?
Wire nuts on 6AWG are a bit 'cumbersome' to say the least. You should use a Multi-Tap which is basically a piece of bar stock with set screws and insulation molded around it. Below picture is available at Home Depot. You'll have to see how it all works out for your particular setup, but you might be able to run the 6AWG wires into the "remote little box with 2 breakers" and fit a pair of 6AWG wires in the taps at the top. The 2nd pair run out to the 6-50 outlet and no multi-tap's required. If you can't do something like this, then you'll have to use the multi-tap's as a "T" running 2 wires on one side and one out the other
You can connect the 6AWG to as many loads as you want (hoist directly and 6-50 outlet(s) and sub panel, etc) so long as it's protected upstream by the proper current limiting device (breaker in your case). Similar answer to the question about feeding a 6-50 outlet with 10AWG and a 30A breaker. Since the 30A breaker is appropriate to protect a 10AWG wire from over heating, you can put a 6-50 outlet on it no problem. You just won't be able to use all 50A before tripping the breaker.
It looks like you can put up to seven 6AWG wires in a 1" EMT conduit per the below table. I'm not sure if the 6-3 that you were looking at was solid or stranded, but I would strongly suggest that you go with stranded individual conductors for this application. Also, please run 4 wires so you have both a neutral and ground.
