110v Electrical Throughout

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r1guy

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Joined
Sep 5, 2018
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7
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USA
Hello all,


Looking at a potential boat for a liveaboard. One item I'd like some feedback on is the boat's electrical. When the boat got its last interior upgrade, the owner rewired the electrical for full 110v throughout. My understanding is that is lights and all. As most boats I have seen are 12v with some appliances on 110 through an inverter, I was wondering if this is ok for a boat or should it be cause for concern?


The generator is out and needs to be repaired (has been out since before the interior upgrade) so I am also not sure if there are other things I should be concerned about when getting the generator back online due to the full rewire to 110. Any idea on the average range of cost for a generator rebuild as worst case?



Thoughts? Not an issue or any red flags with this to be concerned about?


Of course, if I get serious well be bringing in a surveyor but wanted to get an initial read to see if its just something I should walk away from.


Thanks so much!


Regards,
Daniel
 
For anything like basic needs (lights, pumps etc) I would use 12v as it would not requires any voltage conversion and so would be more efficient. In your case I guess it depends on what you have aboard, and if you plan to be mostly at anchor or at the dock with 110v connected.

L
 
How big a boat?

Ted
 
For anything like basic needs (lights, pumps etc) I would use 12v as it would not requires any voltage conversion and so would be more efficient. In your case I guess it depends on what you have aboard, and if you plan to be mostly at anchor or at the dock with 110v connected.


Initial plan is to dock for at least 1-2 years with weekend anchoring. Longer term, would love to be on a mooring during summers. But who knows if that would happen due to practicality of full time work on land.



How big a boat?
Ted


The boat is 41ft, 14ft beam.


Daniel
 
It sounds like the PO was planning the boat to be a dock darling and therefore would always be connected to shore power. If a boat is going to actually be used, it is more efficient to have as much as possible on DC and save the AC for stuff that can not be powered directly by DC. With technology today, it's possible to buy DC versions of almost everything except some large appliances like stoves, washer/dryer, and house size refrigerators. Converting AC back to DC is very inefficient and also generates heat. A lot of heat if the AC to DC converter is cheap and poorly made.



Another issue is that loud hot generator. It is really awful for everyone aboard and nearby to listen to it run all the time. Inverters, depending on their efficiency, will drain batteries fairly quickly when they are expected to handle all the electrical loads requiring the genny to be run often. Oversizing an inverter can be a bad thing. They also have a tendency to produce a lot of heat. The bigger ones can turn a small space into an oven.



I'm sure there are other factors as well. those are just the ones that immediately pop into my head.
 
I would seriously doubt that the boat is 100% 110V AC. There are several things that can't be had in 110V: fresh water pump, bilge and shower sump pumps, most fans, etc.


And it will be impossible to hang out at anchor without a working genset or a substantial inverter with a large battery bank if it all is 110V.



So go through the electrical system and confirm if 110V or not. At a minimum I would change the lights to 12V leds in addition to those mentioned above that almost have to be 12V.


David
 
It sounds like the PO was planning the boat to be a dock darling and therefore would always be connected to shore power. If a boat is going to actually be used, it is more efficient to have as much as possible on DC and save the AC for stuff that can not be powered directly by DC.


From the conversation I had, I do think it was intended to be a dockside condo. And while I expect to be at a dock ALOT for the first year or two I really want something I can have the option to have at anchor alot in the future. So, perhaps this one is not the boat for me. Id have to go into it knowing I may need to upgrade to another boat in the future.


Daniel
 
I would be concerned if the owner changed out anything the was originally 12 vdc. This would include lights, switches and fans. Its pretty difficult to run new wire in a living spaces in a boat.... just feeding existing DC switches with AC and changing out light fixtures with the existing DC wire does not provide a ground conductor to either the switch or the fixture...
 
My alarm bells are ringing. The generator is out to be repaired? Changing all the lights over to 120 without an inverter means no lights at anchor. Did he rewire or take shortcuts by connecting the 12v wires to 120 and change the bulbs? What does the back of the power panels look like?
 
I would seriously doubt that the boat is 100% 110V AC. There are several things that can't be had in 110V: fresh water pump, bilge and shower sump pumps, most fans, etc.


All those can be had in 110v AC. I have installed pumps in houseboats that match those. In this case, I doubt they are AC units.


And it will be impossible to hang out at anchor without a working genset or a substantial inverter with a large battery bank if it all is 110V.


Whole agree there.




So go through the electrical system and confirm if 110V or not. At a minimum I would change the lights to 12V leds in addition to those mentioned above that almost have to be 12V.


:thumb:
David




I would confirm those things voltages as well.
 
Not enough info.

If every fixture on the boat was rewired to 110... Could be a problem.

If every fixture was replaced with a 110 fixture and rewired correctly...maybe no big deal if the lights are LED or can be converted.

12V lighting is simple enough to install...and usually better than where many manufactures place it anyway.

But without diagrams and phcs of the fixtures with wiring.... It's all a guess.
 
I live aboard and cruise. All my lights are 120v. The only 12v I use are radios, nav gear, emergency lights, and bilge pumps. I use an inverter that supplies 120/240 and it's on all the time unless at the dock. Having 120v and 240v appliances & lights are not a problem with a decent inverter and generator.
 
On an 83ft boat a 24/7 genset is unsurprising, on a 40 ft boat it sounds like a major inconvenience. There are reasons most things on a boat are 12v, complemented by "mains" type powered items supplied via shorepower, or genset as required when cruising. Departure from that triggers red flashing lights for me.

You would need a specialist electrical survey,depending how it really is set up. How well it was done would be part of the inquiry survey process. If you want to go cruising, I question if it is the boat you need.
 
While you have repeatedly been advised to walk away from this boat, because of the difficulty of running an all 110v boat, it is unlikely that she is all 110v, and if she is it is inconceivable that someone rewired the boat correctly for all 110v.

You can check if the boat is all 110v by seeing if the there are leads from the battery going anywhere other than the inverter (engine starter?).

As to whether the boat has been correctly rewired 110v and 12v have different color codes, different number of conductors (wires) per outlet, and different required wire sizes. While 22 gauge wire is frequently used in 12v applications I question whether it is permitted in any 110v application. Bay Pelican had 1,000 feet of 18 gauge wire, almost all uses of 110v would have required this to have been pulled and replaced. To have been done correctly to pass future surveys almost every wire on the boat would have had to have been pulled and replaced.

Run, do not walk away.
 
Since the first 2 perhaps 3+ years will be dockside a mostly 120v boat will work best.

HOW it was converted to all 120 is of interest , but should not be a danger as 12V wiring is way oversized for 120V.

Batterys are getting better , inverters are getting better so in a few years you can decide if anchoring O'nite or long term living on the hook is your thing. Refrigeration is usually the stumbling block.

Sadly generators are expensive , but if there are no big power hogs like air cond -24/7 required a 4KW -6KW set should be enough , and if needed 24/7 operation may get more reasonable IF boat noisemaker assemblers copy the RV folks and install inverter sets that have variable speed engines.

How does the rest of the boat survey?
 
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I would look for a different boat. Boats that were built/maintained perfectly are a huge amount of work to keep going, ones that were messed up during construction, or by a previous owner, are a nightmare.
 
110v Boat

I have a Mainship 430 wth a full size fridge/freezer, ice maker, and a bunch of A/C household appliances, gadgets, lights, table lamps, etc.
A couple of years ago we cruised about five hrs away from our yacht club to a popular anchorage to meet up with some friends in their boats for an overnight raft-up. Anchor down, rafted up, settling in with good friends, cocktails coming out, and Low Batt beeper comes on, so we start the genny. No water out of the exhaust indicates trouble. Shut it down, but engine room stifling from two Cats running for 5 hrs, so way to hot to attempt to replace the gen water pump impeller, so no recharging inverter batteries. No AC power and a five-hr run to get back to our dock and shore power. Not popular.
More recently, we went to a nice small harbour about six hrs away and settled in at a float alongside the main dock where we'd been told there was 50A power available. First problem was our 50 Ft 50 A power cord wouldn't reach the power panel, so we pulled out our backup 75 Ft 30 A cable thinking we could make do with no A/C, hot water or stove (all 240 V). The cable reached OK but we couldn't take the shore power. They'd had it rewired recently and installed GFIs on all their circuits. The shore pwr GFIs conflict with our on-board AC GFIs, so the shore pwr breakers trip as soon as pwr turned on to the boat electrical panel. No shore power meant running the genny for a couple of hours each morning before turning on the coffee maker and through the evening - every day. Same thing happens in our boat yard when we plug in to 20 A to run a de-humidifier and air circulators through the winter through our inverter in bypass mode.
All this to say AC boats have their drawbacks. Be aware.
 
If you need to call in a marine electrician to fix that generator, plan on about $125.00 per hour labor rate plus parts. If the generator needs to be replaced, about $7,000 to $10,000 for a 8kw generator plus labor to remove and install. As you can see, this is a major expense.

Easy enough to check what the voltage is on the lights. Unscrew a light bulb and see what voltage is marked on it. A quick check with a multi meter will tell you what voltage the pumps are. Or check the voltage at the electrical panel for the various items.
 
Anything that is not demonstrating to work should be suspect. I have a boat with what amounts to a live aboard capability with all boating equipment fully functional. It has both DC and 120 VAC. I had to revamp the 120 VAC to bring it up to standards and therefore the boat is insured without any exclusions.


Please, email me at rolito_martinez@hotmail.com for some important suggestions.


Rolo
 
I have a Mainship 430 wth a full size fridge/freezer, ice maker, and a bunch of A/C household appliances, gadgets, lights, table lamps, etc..... All this to say AC boats have their drawbacks. Be aware.

How is this an "AC boats" issue? If absolutely everything on your boat was 12VDC you would have the same exact problem, but with a 10% buffer (most inverters run at about 90% efficiency).

Your batteries would still have died, but after 5.5 hours instead of 5.0 hours.

The reality is also that 110/220/230 volt appliances are more efficient than most of their 12VDC brethren, plus less losses in the wiring. So there is probably a 1% or 2% gain there, thus reducing that 10% gap slightly.

Having a boat 100% AC is excellent for larger boats, especially those with heavy load motors (thrusters, windlass, pumps, davits, etc.) but I agree that the OP's referenced 41' trawler is small for full AC. It really serves little purpose and was most likely home-wired. A marine electrician should survey the electrical system.
 
From the conversation I had, I do think it was intended to be a dockside condo. And while I expect to be at a dock ALOT for the first year or two I really want something I can have the option to have at anchor alot in the future. So, perhaps this one is not the boat for me. Id have to go into it knowing I may need to upgrade to another boat in the future.

Greetings Daniel. I would be cautious HOWEVER I'm not entirely against a boat that runs primarily from shore power. You have already stated you intend to be dock bound for at least a year or two.

PROVIDED the wiring for the 120 side is okay, I would be fine with the boat. You've got time to upgrade/change how things are wired over the period you'll be at a dock.

Plan on spending money regardless.
Now I don't want your boat to burn, so be careful in checking the electrical system. However you've got time so slowly change over to what will work better when on a mooring ball or at anchor.

Side Note: Years ago the "best practice" for those that could afford it was to power exclusively via 12-volts/battery power. Now things are changing. With the addition of solar panels and inverters, plus on board generators times have changed. It is not so uncommon any more.

I know at motorsailor that has a 100% electrical galley. They anchor out A LOT. And not just for a weekend. I'm talking a month or three at a time. They even bought an electrical grill for the cockpit rail. All electric boats can be done and is being done today. (Caveat: few can power an air-conditioner without an generator.)

This is the boat with the all electric galley:
IslandTime-SunsetByBridge.jpg

Frankly I thought it odd at first but with further consideration, they do have renewable power via their solar array and a generator. They won't run out of propane. It is a better set-up than at first glance.

And built-in generators with sound shielding are not all noisy critters. Why I hear that the sound of the water cooling genny is entirely drowned out by the air-conditioner running.

Also consider thumping the price a bit. Any time a boat is not Standard, those eccentricities come off the top of the price-tag. As for me, I would be cautious but not totally negative.

Good luck Daniel.
 
I am all electric galley, stove and fridge, MW are all 120vac.
An inverter, you have about 90% efficiency, so you lose 10% in the conversion process.

Lights are a mix of 12 vdc and 120vac.
Of course bilge pumps, built in cabin fan vents, blowers, running lights, electric head, lectrasan, etc... are all 12vdc.
 
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I would love to see an inverter going from 12vdc to 120vac which only has a 10% loss. Everything I've read points to much higher losses.
 
I would love to see an inverter going from 12vdc to 120vac which only has a 10% loss. Everything I've read points to much higher losses.


My thoughts exactly. I think 90% efficiency is pretty optimistic. 85% is very good for an inverter.
 
120V is more lethal than 12V (unless you happen to actually be in the water).
Apart from previously voiced concerns about how the wiring was actually done, I would urge caution if you have a typical (older) boat with many unidentified wire comings and goings. It is much easier and safer to work with 12V, especially in a damp/wet environment. Worst case usually is a bearable shock or small burn, not a heart attack and a body bag! Personally, I would keep 120V to a minimum and only for essential items like AC, frig and water heater (while on shore power), and water maker (though 12V versions are also available).
 
!20vac does not have to be dangerous. I have a lot of circuits GFCI -AFCI protected.
All AC systems are 120vac with raw water pumps of 120vac. You don't hear about people being killed.
 
It is obviously better to have the GFCI-AFCI protected circuits. All I am suggesting is that less is more - the fewer 110V circuits on a recreational boat the better.
Plus you also never hear about people being killed by sharks --- till it happens!!
 
There are strict ABYC standards to keep 120V systems safe on a boat.

Plus there are safe working practices that should be followed.

You take way bigger risks in boating than just having a properly installed and worked on 120V system and appliances onboard.

Having 120V aboard is probably safer than having a gas powered boat.... Everyone with those should give then up?
 

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