Simple Shore Power Installation

[daveyjustin]

Hi. I'm new to sailing and the forums.
I would like to liveaboard, but the boat doesn't have shore power. What's the cheapest way to connect the shore power to the sailboat?

Thanks!

[S/V Illusion]

If I take your question literally, just run an extension from the dock to whatever you want to power. The real issue is how to do it safely at a minimum cost and this isn't the proper way. There are electrical standards which apply similar to electric codes for buildings which require a properly grounded and isolated AC electrical system with breakers both at the shore junction point as well as on each leg inside the boat.

There are a huge number of reference sources including doing a simple google search on boat AC systems which will give you a primer on how to do this at a reasonable cost but if you are not familiar with wiring, it may be a wiser choice to open your wallet and have it done safely.

[daveyjustin]

I've noticed that shore power and standard AC outlets are different. Keeping in mind that this would be a livaboard solution, I will need a contstant electrical source for a heater, computer, and a few other necessities. Can I run a shore power cable into the boat to some kind of adapter with standard appliance outlets?

Forgive the naivety, but thanks all the same.
J

[Sandero]

You want to determine if you want a 30 am or 50 amp service. The former suffices for most boats.

You will need a suitable location to mount the inlet receptacle such as a Marinco. And of you'll need a 30 amp shore power cable (50' is a common length)

Next you'll need some #10 3 wire tinned stranded wire to connect from your shore power receptacle to a main fuse. Blue Seas makes up panels which have 30amp main fuse and as many fused circuits as you want. You may want one for outlets, one for a battery charger or water heater, or micro wave. The you need to wire the devices to the breakers appropriately sized. Obviously you can't have 3 - 15 amp circuits with a 30 amps service or expect to draw that sort of current without tripping the main breaker. You can use the main panel with breakers as switches to energize that circuit you want to use.

What does this cost? I am guessing here:

30 amp Shore power cable $125
30 amp Shore power receptacle $50
3 lead #10AWG $10 - 25
BlueSeas Main panel with 3 breakers - $200
3 lead #12 to recepticles and devices $50
Receptacles and boxes $15 - 20

If you have an inverter you will need a transfer switch BluesSeas is about $175

[sabray]

Don't forget green grounding wire

SV illusions points were good "There are a huge number of reference sources including doing a simple google search on boat AC systems which will give you a primer on how to do this at a reasonable cost but if you are not familiar with wiring, it may be a wiser choice to open your wallet and have it done safely"

[daveyjustin]

Thanks for the advice thus far. I wonder if other boaters have considered the widely available "powerpacks" or "powerboxs" for portable power. I'd like to describe an electrical set up with the costs and ask your opinions. I would like to have shore power professionally installed when I can afford to do so, but for warm sailing months, here it goes...

What I need to power (not simultaneously & apart from cabin lights and running lights):
1. Laptop
2. Toaster over
3. Blender
4. Microwave
5. Hotplate
6. Alarm clock
7. Stereo
8. Printer
9. Lamp

The Folkboat currently:
- limited electrical system
- outboard motor that charges a marine battery, hooked up to a fuse panel for running lights and cabin lights.

What's available:
- Shore power hookup, Dockside 30A 125V

What I suggest:
Marinco Pigtail Adapter 15A STRAIGHT TO 30A LOCKING (105A)
This adapter attached to the dock shore power receptacle, running a standard outdoor an extension cable into the boat.
I would use this cord from the dockside receptacle to directly charge a Duracell Powerpack 600. I would charge this powerpack when I am not on the boat, and then use it's power when on the boat, solely for small electronics devices (ex. charging cell phone and laptop).
When I need to use an appliance that requires more than 480W AC I would use the direct cable from shorepower.
When sailing, I would be limited to a butane stove, and the Duracell powerpack, charged using a solar panel when no shore power available.

If this plan sounds ridiculous and dangerously naive please let me know. I'd really like to get some opinions on this. It's minimalist and roughing it a little, but until I need to run equipment constantly (ex electric space heater in the fall/winter) I think this set up might work in my budget.

[btrayfors]

Davey,

You've got some good advice above on how to do it properly, and this is certainly the preferred way. You need to start saving your money NOW and plan on a decent 120VAC install as soon as you are able.

Meanwhile, your "minimalist" approach could be made to work, providing:

1. that you learn a bit more about electricity and, particularly, about the power requirements of each piece of equipment you plan to use; and

2. you provide at least "minimalist" protection for the power wire coming to the boat, in the form of a circuit protection device.

Both of these things are do-able with very little expenditure.

The items you list in terms of the amount of power they require range from negligible (alarm clock, printer, charging cell phone) to heavy (hot plate, toaster oven, heater). You need to pay CLOSE ATTENTION to the power requirements of each item. A heater alone can consume ALL THE POWER available from a 15A extension cord. Toaster ovens and hot plates can also draw a LOT of current.

Write down the draw of each item, and learn which you could run simultaneously and which you couldn't. Try to stay considerably under the 15A maximum, because at 15A there will be some heating of the electrical cord.

For at least some protection, you need a breaker on the extension cord. The 30A to 15A pigtail you mentioned is just an adapter and, it's very DANGEROUS if you don't learn something. This is because the dock outlet is wired for a 30A draw, while the extension cord will carry only 15A safely. However, if you plug in more than 15A worth of stuff (e.g., heater and hot plate), you could be trying to draw a lot more than 15A thru the extension cord and the dock's circuit breaker wouldn't help a bit. You would cause a meltdown and probably a fire in short order.

The easiest way to mount a breaker in your situation might be to look for a power strip (multiple outlets) which has an integral circuit breaker for 15A. Then, plug everything you intend to use into one of the outlets on this strip. If you plug in too much, the breaker will trip.

You'd also want to find the heaviest, most robust extension cord you can find, e.g., some of the ones used for construction.

Also, you want to be absolutely sure of clean and tight connections. When you plug the extension cord into the adapter pigtail, use good quality electrical tape to tightly tape the connection, both for physical contact and to waterproof the connection.

Understand that I'm not recommending you do this; only that if you absolutely plan to do a "minimalist" system like this you take the above-outlined steps to provide at least some protection for you, your boat, and the marina.

Bill

[GordMay]

The battery is only rated 28 Amp-Hours. This is a TINY battery, with minimal capabilities.

[boatpoker]

The chances of getting insurance (for which you will need a survey) with a jury rigged AC system are slim and without insurance your chances of getting a slip in a marina are also pretty thin.

[David M]

You do not need to spend an excessive amount of money on Marinco brand twist lock connectors. Really good hardware stores have twist lock connectors for much less money. Put some silicon grease on the contacts and you will be fine.

I do have to say that whatever you do should be to ABYC standards at minimum.

[daveyjustin]

Thanks. Hmmm....
Does anyone know a website that has a detailed, perhaps even illustrated break down of shore power installation?

[sushirama]

Your shore power options would depend on you ship power setup. If you have a large battery bank setup with an inverter you can run the boat off of that. Then the shore power just keeps the batteries at full charge. This is how most computer UPS systems work. Youre always running on batteries and your 120v just keeps them charged. Easy and simple but youre limited at dock to what you have underway.

The other option is where you switch your load through a buss system. Plug in, switch to shore power buss and bypass the inverter charging system. This would be the same as if your house power had a genset adapter basically above the main breaker is a switch the "points" to where the power is coming from. This takes a little more time and money to setup and get operational. If youre good and electricity and electronics not hard. If youre not youll need an electrician to do the setup for you.

Also as a note if you need emergency 120v most computer UPS systems run using 12v batteries. You can pull the little battery out and with 10g jumpers run them with a single or banked car or marine battery. A single large car battery can run a notebook for about a week. When you plug the ups in to 120v it will charge a car battery also. Somepeople have used this to enhance the time on thier ups at home or in campers etc.

[boatpoker]

Starting from the shore power pedestal you will need in order of appearance ...

1.) 30amp shore power cord.

2.) One shore power inlet (mounted on the boat).

3.) However many feet of #10/3-wire/tinned/stranded wire to get from the inlet to your new AC panel (not more than 10' from the inlet).

4.) An AC panel with a single pole breaker and polarity indicator or a double pole breaker in which case the polarity indicator is not necessary. Buying a panel with a volt meter is a good idea but not essential. Buy a panel with as many circuits as required (likely no more than 3 on a small boat).

5.) You now need more 3-wire conductor to run from the panel to each outlet.

6.) The first outlet on any circuit must be a G.F.C.I ( pretty much means them all).

7.) The AC ground Must be bonded to the DC ground.

DO not buy ANY parts at the hardware store. You will pay more for marine grade stuff but there are valid reasons.

Good luck

[GordMay]

In addition to the last several (excellent) posts, see also the ABYC standard
ABYC E-11
AC & DC Electrical Systems:

http://www.abycinc.org/committees/e-11.pdf

Note: This is the 2003 edition, which has undegone substantial revision last summer (Aug. 08)

[DeepFrz]

Resources - Blue Sea Systems

Check out the entries
Ten Deadly Conditions to Check for in Your Boat's Electrical System - Part 1

and Part 2

to start with, then read the rest.