[Wooddust]

I am wanting to upgrade my electrical service from 110 to 220. Right now, there are 3 wires running from the main panel in the house to a sub panel in the shed. This is 8 gauge thhn coming off a 50 double pole breaker and going to a panel with no main breaker. Can I just install a grounding rod at the shed and move the wire that's hooked up to ground in the main and hook it up to the other leg on the 50A double pole breaker. Isn't this going to give me 220 and be safe? Thanks for any advice

 

[AllanJ]

I am wanting to upgrade my electrical service from 110 to 220. Right now, there are 3 wires running from the main panel in the house to a sub panel in the shed. This is 8 gauge thhn coming off a 50 double pole breaker and going to a panel with no main breaker. Can I just install a grounding rod at the shed and move the wire that's hooked up to ground in the main and hook it up to the other leg on the 50A double pole breaker. Isn't this going to give me 220 and be safe? Thanks for any advice

Using two conductors and ground you can convert from 120 volts to 240 volts only.

To have both 120 and 240 volts at the shed you need 3 conductors (one of them white) plus ground.

In addition, you need two 8' ground rods at least 6' apart at the shed when you have a subpanel out there.

A bare or green wire in the feed cable or conduit may be used as a ground (equipment grounding conductor) only.

A white wire may be either a neutral or (if no non-green colored wire is available) one of the hot lines of a 240 volt only circuit.

 

[rjniles]

Whay color are your 3 wires? What is the conduit (metal or plastic)?.

You need a 4 wire feed, 2 hots, a neutal and ground. A metal conduit may be suitable as ground.

 

[Wooddust]

Right now I have a black, white and a green wire and it is ran underground through 1 1/4" PVC. Can I not run a red wire and that not give me 220? When you say I need 3 conductors do you mean 2 hots for 220 and another hot for 110? Why do I need 2 grounding rods? Do I need 2 grounding rods and also grounded to the main panel? I'm not meaning to question what you are saying, I just want to make sure I understand exactly want I need to do. Thanks again!

 

[dmxtothemax]

Ideally you should have -

Black = hot no - 1.
Red = hot no - 2.
White = Neutral.
Green = Earth.

If you already have white , black & green.
Then you just need the Red for hot no 2.

Try to keep the earth and neutrals seperate,
This way you can have an gfci in the main panel
which will protect the whole run of cable.

 

[rjniles]

2 ground rods is a code requirement. Also you must keep the grounds and neutrals separate (code) .