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capehorn3
05-30-2016, 07:31 AM
I'm building a shanty boat and am going to have a Honda generator EU2000. Any reading, tips on wiring, safety for 110 volts on a boat?

Garret
05-30-2016, 10:05 AM
Just to take it in a different direction - why not 12 volt? That way you don't have to run the generator all the time - saving $ and noise. Batteries can be charged from an outboard, generator, solar panels or wind turbine.

Through the RV market, most anything is available in 12 volt & if you have to have 110, you can use an inverter. 12 volt LEDs are now available most anywhere & hardly use any power at all. If doing just lighting, a group 27 battery would probably last at least a week.

slug
05-30-2016, 10:25 AM
This is old... Dc wiring

Very good info http://www.kb-kbh.dk/shipslib/el_ombord/12volthandbook.pdf

i did a quick google but couldnt locate any free AC marine wiring assets

ill look again ...or you can do

mmd
05-30-2016, 10:35 AM
Go DC.

genglandoh
05-30-2016, 10:40 AM
This is old... Dc wiring

Very good info http://www.kb-kbh.dk/shipslib/el_ombord/12volthandbook.pdf

i did a quick google but couldnt locate any free AC marine wiring assets

ill look again ...or you can do

Thank you very much for this link.

Here is a short 10 min video about the 12 Volt wiring I have done on my sailboat.


https://youtu.be/J0dLZmjQsgo

Breakaway
05-30-2016, 01:18 PM
Over the years, I have found Nigel Calder's book, Boatowner's Mechanical and Electrical Manual (http://www.amazon.com/Boatowners-Mechanical-Electrical-Manual-Essential/dp/0071432388) a great reference. I use it all the time.

Kevin

capehorn3
05-31-2016, 06:46 AM
Thanks all, I will be using 12 volt for LED lighting, GPS, ect. but will have an AC unit and a micro wave that will need more power. Was specifically wondering if I should run the 12 volt charging line from generator to battery and if that would be a problem given that my motor is also charging battery while under way. Also inverters are an unknown to me, looks like I would need a large battery bank just to run a coffee maker?

nedL
05-31-2016, 07:20 AM
That's going to be a small microwave. We have a 3K backup generator at our house and the microwave is the ONLY thing that can't be used (oil fired boiler heat, 220 well pump, electric stove all ok).

The Bigfella
05-31-2016, 07:26 AM
I run the microwave on my boat... but the diesel genset has a 20hp engine driving an 8.5kVa generator. It ain't small.... or quiet.

Make sure you install an earth leakage device... there's so much more opportunity for things to go wrong on a boat.

When working with power tools, I tie the electrical lead to something, so that if I fall overboard, the plug will pull out before I hit the water. I've gone in once... carrying a $400 powertool... but it wasn't plugged in at the time. I lost the tool... and a pair of $600 eyeglasses too.

CapnJ2ds
05-31-2016, 07:26 AM
In a house you must use a registered electrician. In a car an autoelectrician. On a boat the village idiot can do the wiring - and frequently does.;)

Phil Y
05-31-2016, 07:28 AM
Is that genny big enough to run ac? Start up draw in particular can be quite a bit more than ordinary running.

capehorn3
05-31-2016, 09:40 AM
Looks like it will, very small ac, need to hook it up to my kill-a-watt to see start up amps.

Wavewacker
05-31-2016, 11:02 AM
Last year a couple of kids were killed swimming beside a dock when they touched the dock, faulty electrical wiring on a houseboat.

110/120V AC, you don't have a copper ground rod on a boat in 6' of dirt, you need an electrical ground. Are you running 2 or 3 phase, your Gen set should have the ground circuitry.

If you're running different gen and alternators, you need a battery isolator that only allows one source or multiple sources for power, you can cook your battery otherwise.

Watch out for cheap inverters with electronics, lap tops, sensitive equipment, you should have a sine wave inverter for steady reliable power. It's better just to use DC.

Fridgedaire has a new small window AC, 5000 btu, at 650 running amps, something like 850 surge, very efficient but the surge kicking on the compressor can double on an AC from their running amps. My microwave needs 1250 amps.

I don't care for the thought of running interior coax by itself in a wet environment, I'd underground coax with electrical plastic conduit for all runs, fused separately, glued and screwed to the box, the only extension cord I'd have would be for my shore power. I don't know if there is a special marine coax, there may be, whatever is correct. Just some feedback :)

Woxbox
05-31-2016, 11:19 AM
And as to the battery overcharge question, yes, you can damage it if you let the genset and outboard pump juice into it uncontrolled. So you need a charge controller that will take two sources. If you really want the whole works, you can install a controller/inverter unit that will also allow you to plug into shore power, too, so you don't have to listen to that generator all night when you're at a dock. But be prepared for sticker shock.

Garret
05-31-2016, 12:57 PM
And as to the battery overcharge question, yes, you can damage it if you let the genset and outboard pump juice into it uncontrolled. So you need a charge controller that will take two sources. If you really want the whole works, you can install a controller/inverter unit that will also allow you to plug into shore power, too, so you don't have to listen to that generator all night when you're at a dock. But be prepared for sticker shock.

Or - use an inverter that has a built in charger. I have the Prosine 2500 watt inverter that charges up to (IIRC) 130 amps @ 12 volts. It is completely configurable to different battery types - charging them exactly as the manufacturer intends. Roughly $1500US for the complete unit. Much less expensive than 2 separate units & takes up less space too.

As far a batteries go: I have 3 8D Gels. They will run the boat (12 volt refrigeration, electric water pressure, lights, computer(s), etc.) for several weeks when we're on board. I have left the boat with the refrigeration on for over 3 weeks in the summer & gotten back to batteries doing just fine charge-wise.

mmd
05-31-2016, 01:23 PM
I did not realize that you were building a live-aboard houseboat when I suggested that you go to DC systems exclusively - I imagined a shack on a barge with a moanin' chair and fishing pole against the bulkhead on the foredeck. Sorry.

Albeit on a small scale, you are describing a mixed-source, mixed-current, on-board marine electrical system. Despite its small size, you will encounter all the issues (and many of the costs) that we do when we install the same type of electrical system on the commercial fishing boats that we build. Issues like stray current, ground faults, cabling & cable terminations, etc. And don't forget lightning protection. It can be done by amateur builders such as yourself, but educate yourself, please. An AC system on board can be deadly, as Wavewacker and The Bigfella have alluded to.

I would recommend that you buy one or all of the books mentioned above (I personally refer to "The Marine Electrical and Electronics Bible - A Practical Handbook for Cruising Sailors" by John C. Payne), study them well, then draw up a one-line schematic of what you want to achieve and have the design vetted by a competent marine electrician. preferably one accredited with the American Yacht and Boat Council (ABYC).

For simplicity's sake, I would suggest that the AC system be completely independent of the DC system, and have the DC system recharged by the outboard alternator and/or solar panels, and keep the AC genset reserved for A/C and microwave duties. If you do opt for a shore power installation, consider very carefully before you disregard a shore-power isolation transformer. They are costly, but will save you a world of hurt should something go wrong between you and the dock outlet.

Finally, use proper marine cables & panels - domestic wire & equipment from Lowes may be less expensive, but it is not the same!

Wavewacker
06-01-2016, 07:30 AM
And, as to storage batteries, check out the advantages of 6V golf cart batteries wired in series for 12v. :)

The only time your 12v system will be close to 110/20v will be in the inverter, I'd never use romax house wire for 12v simply because I'd never mistake them for 120v, even if the gauge was correct for the run.

I'd also not run electrical lines under any plumbing line, that's asking for condensation or any leak to drip down on your wiring, perhaps then to an outlet or fuse block. Same with any drip tray from a fridge being higher than your outlet, if that can't be avoided I'd use a drip loop (tied off) on the power cord to the outlet.

I'd certainly follow the suggestions by mmd, which reminds me I should get that book, and meet or exceed those standards, my comments come from campers, not boats, but I'm sure they are applicable. :)

slug
06-01-2016, 07:38 AM
Google english canal boats electrical. On the internet somewhere is a good resource describing best practice for electrical systems on these boat.

Garret
06-01-2016, 07:40 AM
There are 2 big reasons to not use Romax: 1) it is solid, not stranded & therefore does not deal well with vibration/movement & 2) it is not tinned the way real marine wire is & will corrode very quickly.

I've found batteries intended for electric floor sweepers (I use L16's in my home system) to be the least expensive when looking at cost/amp hour. In the boat I use 8D's because they fit better - though slightly more expensive.

ulav8r
06-01-2016, 04:59 PM
Last year a couple of kids were killed swimming beside a dock when they touched the dock, faulty electrical wiring on a houseboat.

110/120V AC, you don't have a copper ground rod on a boat in 6' of dirt, you need an electrical ground. Are you running 2 or 3 phase, your Gen set should have the ground circuitry.

If you're running different gen and alternators, you need a battery isolator that only allows one source or multiple sources for power, you can cook your battery otherwise.

Watch out for cheap inverters with electronics, lap tops, sensitive equipment, you should have a sine wave inverter for steady reliable power. It's better just to use DC.

Fridgedaire has a new small window AC, 5000 btu, at 650 running amps, something like 850 surge, very efficient but the surge kicking on the compressor can double on an AC from their running amps. My microwave needs 1250 amps.

I don't care for the thought of running interior coax by itself in a wet environment, I'd underground coax with electrical plastic conduit for all runs, fused separately, glued and screwed to the box, the only extension cord I'd have would be for my shore power. I don't know if there is a special marine coax, there may be, whatever is correct. Just some feedback :)

Your equipment does not draw 650-1250 amps. 1250 Watts would be a large microwave. 1250 watts/120 Volts = 10.42 Amps; 1250 Amps*120 Volts = 150,000 Watts.

Cogeniac
06-01-2016, 07:54 PM
I don't know if anyone else recommended this, but Charlie Wing's book "The Boat Owner's Electrical Handbook" is really informative. It includes lots of illustrated examples.

https://www.amazon.com/Boatowners-Illustrated-Electrical-Handbook-Charlie/dp/0071446443?ie=UTF8&*Version*=1&*entries*=0

ranga
06-02-2016, 05:43 AM
I'd never use romax house wire for 12v simply because I'd never mistake them for 120v, even if the gauge was correct for the run.


Have came across wiring on a boat where some of the 12V stuff was in romex and some of the 240v was done using what the rest of the 12V stuff was done in. That was rather nasty to find, thankfully I (or a kid as it was a scout boat) didn't find it the hard way.

Garret
06-02-2016, 06:33 AM
Ranga - you'll want to clean up that post (the word before "nasty") - the moderator will delete the post & possible others of yours for the language.

ranga
06-02-2016, 06:48 AM
Ah thanks.

Garret
06-02-2016, 07:02 AM
Yoobetcha!