Pond Boss Forums INTRO Questions & Observations 115/230 volt at dock

I've seen several posts with questions about running power and thought I would offer what worked for me.

I ran a piece of #10 direct burial from the house to my dock (about 350 feet) to power my irrigation pump. The pump runs on 230v, so I ran 10/2 wire. I didn't need a neutral and 10/2 is considerably cheaper than 10/3.

This was a bad move because without the neutral wire, I didn't have 115v for a light, radio, or utility outlet at the dock. So I bought a 115/230 volt outdoor rated transformer for $38 on eBay. It is rated for 500 watts, enough for anything I might need at the dock, but they are available in larger sizes. Be sure to shop around, these things can be very pricey, but can be found very cheap.

This is the one I got for $38

So now I have both 115 and 230 volts available at the dock and only had to run a single piece of two conductor wire which saved me more than the cost of the transformer. I might have been able to run #12 instead of #10 since the feeder is 230v, but this is not a good place to cheap out.

Simply, the transformer input is 230 volts, the output is two hots, each 115 volts, plus a neutral.

Hope this helps somebody.

Jersey,

I don't know much about electricity but my electrician (My dad) installed a GFI on mine at the pond in case of the unforseen when it comes to water. Do you have that? If not I would suggest getting it.

How deep is good enough if you're sure there will be no more digging in the future?

I must have scared Jersey away Bob.

From having dug around utilities, its insane how shallow the electric company buries their wires. Anywhere from 6" to 12" IME. So I guess it would work for the non professional.

If a local deep ground rod was driven, there would have been 2 115 vac circuits with the ground as neutral to each hot line.

Sorry for the late reply. I don't have internet at the house (dial up does not count).

The buried wire is about 4'. I ran it in the same ditch as the geothermal pipes.

Technically, it might work to use the ground wire for neutral, but that is a rule that I don't want to break. And you couldn't use a GFI outlet if you do this. If you put a ground rod at the end of the run (by the dock) you would have the potential for a very bad ground loop situation, because the other end of the wire is already grounded at the panel. Believe me, before I came up with the transformer idea, all of this crossed my mind. There are just too many dangerous problems associated with using ground as neutral.

Jersey, I see. You actually got a 0.5 kva isolation transformer for $38 bucks. Very good deal. I fugured it was an auto former. Did you ground the case and/or neutral? Good info.

The center tap of the secondary, which is neutral, is grounded.