Electrical Question

[dknarnd]

A piece of property I purchased had a mobil home on it and I removed the mobil home. The power to the home was plugged into a box on the meter pole with a 4 prong 125/250V 50amp plug and now I am going to build a small shed there. Can I make some sort of extension box that uses this 4 prong plug and gives me 110 power to run my compressor and saws when I build the shed?

I am going to sit the shed over the septic system and also hook up to the well so that I can use and preserve these items for future use.

If I didn't have to go about 200 yards up the road to get there I would build it at the garage then just hook up and drag it.

[hayden]

Yes, you should be able to. The plug provides 120/240 V service plus a ground. This is called "single, split phase" power. On a mating plug the connections should be labeled (perhaps inside the plug shell) as follows:

L1 - One of the two hot lines
L2 - The other hot line
N - Neutral
G - Ground

Connecting between N and L1 or between N and L2 will give you 120V. Connecting between L1 and L2 will give 240V. The Neutral allows you to "split" the 240V L1-L2 power in half to get 120V, hence the term "split-phase".

To create a circuit for your compressor and other power tools you will need some sort of small sub-panel to take the 50A circuit and create a 20A cicuit. Do not under any circumstances connect to the 50A circuit directly without an intervening 20 breaker or you will put your compressor and yourself at risk of distruction.

Rather than risk creating a hazard for yourself and others, I'd suggest getting a friend who knows how all this works to help you, or hire an electrician. No offense intended, but if you are asking this question you are probably not qualified to do the job without someone checking it carefully. Personally, I think your best approach would be to replace the 50A receptical with an outdoor sub panel, 20A breakers, and one or two outdoor outlets. When you are done with construction, you can re-route the power to inside the shed, or leave it outside.

[Mike058]

You can't really use the 50 amp mobile home panel to power tools. It's not to code or safe. Like Hayden said, you can't plug tools into any circuit that has more than a 20 amp breaker protecting it. Swapping the mobile home panel for a small outdoor panel wouldn't be hard for someone that's experienced. Do it wrong and you could end up killing someone or starting a fire down the line. There are a lot of details to worry about. Grounded wires versus grounding wires, when to bond a nuetral wire and when to leave it alone, making sure there's a proper ground at the box etc. Consider getting an electrician out there and have him take a look at what you want to do.

[RonL]

Jim

You can make an extension cord using 6-4 soow. Use a NEMA 14-50 plug on one end and a "California style" twist lock connector on the other. Run it to a "spider". The "spider" is a power distribution box that has 20 amp 120V ground fault protected outlets and a 30 amp 240V outlet. It also has a 50 amp feed through outlet to daisy chain the spiders ( or in my case, to connect my inverter welder). The unit I have is made by Leviton and is called "the box". Northern tool also has a unit listed. They are not cheap but making up a panel with similar connectors and gfci breakers would not be cheap either. They are UL listed and approved by OSHA for work sites. I would take a picture of my set up but it is up on my property in New Hampshire. I'll be up there this week. I'll take pictures and post them.

RonL

[dtd24]

I would go the route of the sub panel box myself. Very simple and more permanent than the spider. If you are going to a shed you can use an interior box which is cheaper.

Mike nice avatar!!!

[dknarnd]

Ok sounds like this is a job for my uncle (the electrician) so I'll ask him to make something up for me. After the shed is finished I want to install the box inside to power the submersible pump, a light or two, and of course an outlet available for whatever. Actually I may install a small water heater and make an outside shower some day!

I don't mind adding a new circuit to a panel for lights and outlets because I have worked with my uncle enough to handle this pretty well but when you get into the larger amps / voltage I get a little uncertain and if I'm not 100% comfortable with it then it's not for me to do. I like to be self sufficient but I like being around to do things even better so I'm not afraid to ask for help.