Electric question

georgepds said:

I need two 20 amp, 110 volt lines out in my shed. Can I run a single 20 amp 240 volt line out to it and then split it?

What do I need to do it to code ?

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What about this? Each hot is a different circuit. I’m not an expert, so I don’t know what code says about sharing a ground and a neutral on separate circuits.

I think you run a 240 volt circuit with two hots, a neutral and a ground out to a small subpanel and then feed the two circuits with two 120 volt breakers.

I am not an electrician, but it makes sense to me.

georgepds said:

Ok thanks

If I understand , run a 3 wire with two hots and a neutral, than run an extra neutral

So I need a second set of breakers for each 110, doesn't the 240 breaker on the main panel cover both sub circuits... won't it trip if either of the hot lines exceeds 20 amps

But I got the main idea..

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You only need one neutral you can split it off out in your shop/shed to the separate plugs/lights. You would be better off to put a small panel in and put a extra set of breakers in for each outlet. Why do you need 2 dedicated 20 amp lines? Depending on local code you can run up to 8-15 outlets/light of one breaker. To do it to code you need a electrical permit and a electrician. Anything goes wrong your insurance may not cover you if a permit was not pulled. How far away is the shed? You will also have to size the wire according to your distance the farther away the bigger the wire. Also if anything is being buried it will need to be underground armor cable or put in conduit.

zrock said:

You only need one neutral you can split it off out in your shop/shed to the separate plugs/lights. You would be better off to put a small panel in and put a extra set of breakers in for each outlet. Why do you need 2 dedicated 20 amp lines? Depending on local code you can run up to 8-15 outlets/light of one breaker. To do it to code you need a electrical permit and a electrician. Anything goes wrong your insurance may not cover you if a permit was not pulled. How far away is the shed? You will also have to size the wire according to your distance the farther away the bigger the wire. Also if anything is being buried it will need to be underground armor cable or put in conduit.

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My understanding is that when a subpanel is installed, the ground and neutral needs to be kept separate all the way from the main panel to the subpanel. Generally a subpanel comes with two bus bars, one is intended for the neutral bus and can be installed either isolated from the panel chassis or tied to the panel chassis. In this case, the neutral bus is isolated from the chassis as the house neutral should only tie to ground in one location in the main house panel. The ground bar is tied to the sub panel chassis.

The point of contention is where the ground bar is connected to. Some just drive a local ground at the subpanel, others run an extra ground wire with the two hots and neutral and connect the subpanel ground bus to the main panel bus. My understanding is the proper method is drive a local ground rod tied to the subpanel and tie it into a bare ground wire going back to the main household ground rod preferably being routed outside the house. The reason for this approach is if there is a lighting hit at the remote panel. In this case, either a lack of a local ground rod at the panel or direct tie to the main house grounding point can cause the lightning to flow to the best ground which is in the main panel. This introduces high currents in the wiring back to the main panel possibly causing a fire in the house. By installing a secondary ground source at the subpanel tied into the main ground point there is no reason for the high current flow through the wires as the ground points are at equal potential. Even if there is current flow between the grounds they will flow in the bare copper wire that is run around the house to the main ground point.

I expect a lot of folks dont realize that just adding a couple of outlets in a remote building has the potential for burning down the house.

Lots of code violations in this thread. I don’t mind code violations where nobody gets hurt like too little insulation but in this case you can hurt somebody.

from your house the romex should stop. junction that and tie in your 10/3 uf cable or pvc pipe into the junction box if it is a 150 foot run then change the wiring to 8 gauge. run this to a small panel in the shed then pull the to twenty amp circuits from that box. yes you will have to drive a 8 foot ground rod outside the shed and tie that into the ground bar of the shed sub panel with 6 gauge wire. the house panel will have a two pole 30. that's it. the pvc pipe or uf cable needs to be 2 feet down in a trench

This Old House had a segment on running electricity to a shed. Don't think it was 240, though. But, you can get some ideas.

https://www.thisoldhouse.com/how-to/how-to-run-underground-power-to-shed

fbelec said:

tie in your 10/3 uf cable or pvc pipe into the junction box if it is a 150 foot run then change the wiring to 8 gauge.h

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Changing to #8 will do nothing, your current will still be limited by the 10/3. If you're running 10/3, stick with 10/3 for the garage space as well.

the 8 gauge will have less loss over a long run to the panel. Then wire the area as normal

The.Devo said:

Changing to #8 will do nothing, your current will still be limited by the 10/3. If you're running 10/3, stick with 10/3 for the garage space as well.

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I think he meant 10/3 for the run unless it's that long then change the whole run to #8.

Important that once you exceed one 20 amp circuit to the shed you’re putting in a full sub panel. Sub panels require 4 wire feeds now.

Do you really need more than one circuit? Whatcha doing out there that can’t get done with just 2000 watts?

festerw said:

I think he meant 10/3 for the run unless it's that long then change the whole run to #8.

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yup. and the only time it is crucial is when you pull a heavy load. lights and a few low power outlets no problem. if you plan on making the shed the house pool pumps that's where the next size up comes into play