Build my own Shore Power Dock pedestal

[Hammer]

I don't want to spend $700 on a dock pedestal and another $400 to have a marine electrician wire it up.

I have just added a dock behind my house and want to build my own shore power solution. I had an electrician run two 30 amp lines to a 4x4 post at the edge of my concrete dock. Plumber ran water and attached a hose bib to the post and the water is running. Now I am looking for advice on how to get to next step with electric service.

The two 30 amp circuits at the dock have breakers in the main house panel. The wires from the house are now terminated in a metal box attached about half way up the 4x4 post. There are no outlets, just the capped wires.

Looking for help from the right person who has installed their own solution Perhaps you can share what FD boxes you used, what weatherproof outlets, what weather proof breakers and how you put it all together.

I can do indoor wiring, but have no experience setting up a shore power solution on a 4x4 post. And I am not familiar with what components are necessary.

I've reviewed the Hubble weatherproof FD box, the hubble outlet weatherproof outlet cover, and the twist lock outlet. It looks like I could do the outlets with two weatherproof FD boxes, but not sure that is the best approach. Also, I can't find any information on adding a breaker or even finding a 120v 30 amp marine breaker.

Any guidance would be most welcome.

Thanks

 

[DavidM]

Here is what you can do. Presume these two circuits are not on opposite phases and you are not trying to wire up a 240V 30A outlet.

Get some direct burial 10 gauge two conductor with ground cable and run it from your post's junction boxes to the new location. Use a short length of 3/4" pvc conduit from the bottom of the boxes to 1' below grade. Run the cable 1' below grade to meet code.

At the dock there are no cheap solutions so the Hubble box is probably the best way to go. I have seen metal outdoor boxes used but these are not designed to deal with a shore power cable sticking out. Run the direct burial cable up to the box through another 3/4" conduit Hubble outlet.

A somewhat better way is to run conduit underground and then pull the new cables which don't have to be direct burial type. Not much better IMO.

If you can do indoor wiring you should be able to do this.

David

 

[Hammer]

Thank you for the info.

I am employing two 30 amp and not trying to achieve 240.

To your point of underground cables running, I am not going to have to run cables as the current 4x4 post is close enough to the boat and will be the service point for the outlets. I can wire the two hubble boxes with PVC conduit.

Have you a recommendation about a breaker? All marine pedestals have their own breaker on each circuit. I am wondering if there is a weatherproof marine breaker that I can employ on each circuit that can double as an on and off switch. I can't seem to find any info about 120v 30 amp marine breakers.

 

[Alaskan Sea-Duction]

Welcome Hammer to TF. Good luck on your project.

 

[Comodave]

I have pretty much the same setup that you do. I got a Square D box, 2 Square D GFI 30 amp breakers and 2 RV outlet boxes. Built a wooden box. Put the Square D electrical box in it. Wired the 2 circuits into the Square D box. Ran each circuit through the side of the wooded box into the RV outlets. Use a 30 amp RV to marine adapter on each shore power leg. It has worked well for 6 years now. The only issue could be that the household style GFI breakers trip at 6mAmps of leakage. Marine GFIs trip at 30 mAmps. So the household GFIs are more sensitive. This can be good or bad. It is good because if your boat will work on 6mAmps of leakage it will work easily on 30mAmp breakers. The bad is if your boat has current leakage, and most older boats do, then it will trip the breakers, but it would probably trip the marine GFI also. Our boat would trip the GFI as soon as I plugged it in. I had to rewire most of the AC side since all the neutrals were on the same bus bar. But once I got it fixed so it would work on my dock it has worked everywhere that has GFI on the docks. Sorry the photos loaded sideways.

 

[Comodave]

I also added some 15 amp outlets on the dock for miscellaneous usage. That is the 3 rd breaker in the box.

 

[Hammer]

Love the box idea. I had not thought of that. By using the GFCI breakers you decided not to have an off and on switch. Is that correct?

 

[Comodave]

I just use the breakers as a shutoff.