DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Electrical (
-   -   120v for shed from 240v HotTub circuit? (

MrMark 04-04-2009 07:05 AM

120v for shed from 240v HotTub circuit?
I have a 240v circuit going to a subpanel which houses a 50amp breaker. I want to create a 120v circuit going to a storage shed, 1 light and 2 receptacles. My question: Is there anyway to run the circ straight off the subpanel by only taking power from one side of the breaker? I want to keep the hot tub powered if possible. There are no more open spots in the main panel. Not sure if I am asking the right questions so please correct me if wrong.
Obviously I am not an electrician so please be gentle :)

AllanJ 04-04-2009 07:18 AM

If this is a "plain" 240 volt circuit (no neutral) then you cannot get 120 volts out of it. You may not use one hot and ground as hot and neutral for your new 120 volt circuits.

In addition, if you tapped off of a 50 amp circuit (or any circuit breakered at more than 20 amps) you must go through a subpanel with 15 and/or 20 amp breakers protecting your "sub-branch" circuits for lights and receptacles.

kbsparky 04-04-2009 07:20 AM

Not if you connect directly to that 50 Amp breaker. :no:

You might be able to install a 15 or 20 Amp single pole breaker in that outside sub-panel for your shed circuit, provided you have a neutral conductor present, as pointed out by AllanJ. :yes:

Not enough space in the hot tub panel? :(

Then install a larger one, and then you should have sufficient space. :thumbup:

MrMark 04-04-2009 01:06 PM

120v for shed from 240v HotTub circuit
I want to thank the parties that responded to my questions!:thumbsup:

The neutral or white going to the subpanel at the hot tub is attached to a buss in the main panel along with all the other white wires. What indicates a 'neutral' versus a 'ground'? If there is no neutral, I should be able to use either the red or white wire as one since I have disconnected the 240v circuit completely.
This is what I have done so far. I pulled the double pole breaker from the main panel and I was just going to install a 20 amp single pole breaker and use the black line for power; the red is just extra at this point. I also eliminated the 50 amp in the subpanel at the hot tub.
I now have another question - assuming everything is ok at this point. :thumbup:

Can I use one side of the twin pole breaker for a 20 amp circuit and just leave the other one off and disconnected?:)

J. V. 04-05-2009 12:01 PM

How many spaces/spare slots do you have in the sub panel? If you remove a double pole breaker you are left with 2 single pole slots. Thats 2 - 120 volt circuits available, What is the current rating on the tub? Is it on grade or above grade?

The tub requires it's own GFCI circuit and it cannot be interrupted. Use PVC conduit all the way.
Severe injury or death may result from a non-compliant installation. I think you should, at the very minimum is get an estimate.

AllanJ 04-05-2009 01:47 PM

The ground is a bare wire or a green covered wire or sometimes the conduit itself. It goes all the way back to the main panel with the hot wires.

All 120 volt circuits are fed with one hot wire and use the neutral as the current return. You can keep the 240 volt circuit running with the red and black wires and use one (either) of the hot wires together with the white for a 120 volt circuit with its own breaker in the subpanel.

The collection of white wires should be neutral and not ground. All neutral wires must be white and may be connected to a buss (buss bar) in the panel. That bus should be attached to the panel with plastic brackets i.e. have no metal to metal contact with the panel. Neutrals and grounds are kept separate everywhere except at the switch (or main breaker) that turns off the power to everything.

There should be a ground buss at the subpanel that is fastened directly to the panel or has a wire or strip from it fastened to the panel.

Yes you can use one side of a twin pole breaker (of the proper amperage) and leave the other side disconnected (you can use that later).

Some 240 volt only circuits use both the black and white as the hot wires and have no red wire. The white wire here should have a band of red or black at each end but sometimes is not so marked. It must not be attached to the neutral bus unless and until the entire circuit is changed over to be 120 volt only and any colored bands on the ends covered with white tape.

MrMark 04-06-2009 12:43 AM

Thanks everyone!
I want to thank everyone for their input. I put in a single pole, 20 amp 120v breaker in lieu of the 240v and just ran it directly to the shed. :thumbup: I will deal with the hot tub issue later, it needs repairs anyway:( Hope yall have a nice day.

All times are GMT -5. The time now is 01:20 AM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1