New boat - 110v or 240v ?

[Dockhead]

Originally Posted by valhalla360

Personally, I would be nervous of a 50' run of cabling with multiple hidden connections in a corrosive marine environment pulling 450amps. Of course, this assumes you have a backbone cable run with branches at each device locations. If you do a dedicated continous cable, that helps but also adds to cost and results in a duplicate DC electrical system.

No reason you couldn't do it that way, but all the boats I've ever bilge-dived in had dedicated continuous cables all the way from the batteries to the thruster, or from the main buses near the battery bank. In my case with a slight variation -- one junction box with 800 amp breaker. So yes, you get duplicate cabling, but for the reasons you state, it would be very undesirable to have breaks and connections in such high amperage cabling. That would be a problem (if no a fire) waiting to happen, wouldn't it?

[Hartings]

OK - thank you for your valuable input

By way of further background - this is the electrical system on the the 'stock' boat -

Quote

Batteries
4 X 8L16 Deep Cycle 6V Marine house batteries (740 amp hours) housed in enclosed fiberglass cabinet in centre foredeck locker
3 X Group 12V for engines and genset
Victron Blue Power Panel VE Net monitoring system
Solar Panels
4 X 304 Watt solar panels recessed into hardtop with Victron Bluesolar regulator as required for solar panels

7.5KW Onan generator

Victron Inverter
Victron MultiPlus 3000-watt power inverter and battery charger located under main settee with control panel at main distribution panel

Shore Power
2 shore power inlets c/w shore power cords 30amps each

12V DC Circuits
24, 5 – 15amp circuit breakers located at the distribution panel with Ammeter/
Voltmeters on panel
12V outlets located 1 at helm, 1 at nav station, 2 at galley.
USB outlets located 1 at nav station, 1 at each cabin
110V AC Circuits
All AC circuits have breakers as required (main, 5 std., spare). Ammeter is on electrical panel
110V outlet located 1 at entertainment area, 1 at nav station, 1 at each cabin, 1 at each head, 3 at galley, 1 at Washer dryer.

Unquote

I am asking them to quote me for changing the house battery system to Lithium and so far they have quoted USD20,000 for 4 x 200amp including new regulators and alternators - I think I would like to have 1000 amps

With the new lithium capacity am I right in thinking that the generator set becomes almost redundant as I can run the electrics on the boat from the lithium (charged via the solar predominantly and the alternators and / or generator when needed ?). Would I have enough dc juice to run the aircon -3 zones 1x 18000 BTU and 2 x 8000 BTU ?

Going on from this the advice here suggests that I may be better served by asking the yard to make it a 24v system (rather than the existing 12v)

And finally - I agree to their offer to make it a 240v system free of charge with an additional separate engine battery charging unit which can utilise 120v short power as and when it is available and needed ?

I suspect I have not got this right at all and therefore look forward to being told so.....

PS - its a Cat so I don't need a bow thruster.......

[noelex 77]

Originally Posted by valhalla360

Personally, I would be nervous of a 50' run of cabling with multiple hidden connections in a corrosive marine environment pulling 450amps. Of course, this assumes you have a backbone cable run with branches at each device locations. If you do a dedicated continous cable, that helps but also adds to cost and results in a duplicate DC electrical system.

But a bow thruster battery increases rather than decreases the number of connections, as well as the overall complexity and number of failure points.

[Dockhead]

Originally Posted by Hartings

OK - thank you for your valuable input

By way of further background - this is the electrical system on the the 'stock' boat -

Quote

Batteries
4 X 8L16 Deep Cycle 6V Marine house batteries (740 amp hours) housed in enclosed fiberglass cabinet in centre foredeck locker
3 X Group 12V for engines and genset
Victron Blue Power Panel VE Net monitoring system
Solar Panels
4 X 304 Watt solar panels recessed into hardtop with Victron Bluesolar regulator as required for solar panels

7.5KW Onan generator

Victron Inverter
Victron MultiPlus 3000-watt power inverter and battery charger located under main settee with control panel at main distribution panel

Shore Power
2 shore power inlets c/w shore power cords 30amps each

12V DC Circuits
24, 5 – 15amp circuit breakers located at the distribution panel with Ammeter/
Voltmeters on panel
12V outlets located 1 at helm, 1 at nav station, 2 at galley.
USB outlets located 1 at nav station, 1 at each cabin
110V AC Circuits
All AC circuits have breakers as required (main, 5 std., spare). Ammeter is on electrical panel
110V outlet located 1 at entertainment area, 1 at nav station, 1 at each cabin, 1 at each head, 3 at galley, 1 at Washer dryer.

Unquote

I am asking them to quote me for changing the house battery system to Lithium and so far they have quoted USD20,000 for 4 x 200amp including new regulators and alternators - I think I would like to have 1000 amps

With the new lithium capacity am I right in thinking that the generator set becomes almost redundant as I can run the electrics on the boat from the lithium (charged via the solar predominantly and the alternators and / or generator when needed ?). Would I have enough dc juice to run the aircon -3 zones 1x 18000 BTU and 2 x 8000 BTU ?

Going on from this the advice here suggests that I may be better served by asking the yard to make it a 24v system (rather than the existing 12v)

And finally - I agree to their offer to make it a 240v system free of charge with an additional separate engine battery charging unit which can utilise 120v short power as and when it is available and needed ?

I suspect I have not got this right at all and therefore look forward to being told so.....

PS - its a Cat so I don't need a bow thruster.......

I would suggest getting qualified professional help on this -- these are important and complex decisions.


For whatever little it may be worth, my amateurish opinion about this configuration is the following:


1. I would definitely go with 230v and 24v UNLESS you plan to be mostly in 110v countries, in which case 110v and 24v. The reasons have been adequately discussed. Add a separate 110v charger (like Victron Skylla) if you will be in 110v countries less than most of the time.



2. You ask about deleting the generator. This is a WHOLE other conversation. Personally, I would find it silly to have THREE diesel engines on a boat less than 100 feet long. Whether solar and a large bank is enough to run air conditioning is a numbers question -- you need to do a proper power budget based on realistic yield from solar. You can't just ask someone if "there's enough juice" -- you need to run proper numbers and do proper calculations. But the "no generator on an electrical power intensive boat" issue also implicates the main engine driven alternators. I personally generate a great deal of power with a 100 amp, 24v school bus alternator on my single main engine, nearly enough to run my boat on. I can run my washer/dryer or electric cooking off this via the Victron inverter. If I were you, I would specify large, high quality, high capacity second alternators on BOTH main engines. If they are big enough to put a decent load on the engines, then this can be more or less a complete substitute for a separate generator, in my opinion.


3. One nominally 3000 watt Victron inverter/charger is NOT nearly enough to run all your AC gear off the inverter, and the charger part is not nearly enough to charge a 500 amp, let alone 1000 amp lithium bank. You need probably three of these, arranged in a gang. That would be 210 amps of charging. I have this exact inverter on my boat, and it is good for not much more than 2000 watts continuously, and less and less in hot weather -- it is very sensitive to temperature.


4. You don't mention control systems. You need to dive into this and specify appropriate control systems including battery monitors etc. etc. etc. If you will be using lithium, there are complicated questions concerning how to control alternators and chargers -- see separate threads running about this right now.


5. There's a guy on here called CatNewBee who has a system similar to what you're talking about here. He is very knowledgeable and could give you a lot of useful advice, if you can make friends with him. I'd send him a case of beer if I were you.

[Hartings]

Thanks for your input - I will ask the yard and see what they say on these issues.

[Kenomac]

We own two boats, one with a 450Ah house bank and 10kw 120/240v 60hz Westerbeke generator, and another with a 840Ah bank and Onan 12.5kw 230v 50hz genset. Both 24v and flooded lead acid batteries.

I have zero problems, and spend zero amount of time fussing with electrical power and power storage issues. Zero... ongoing costs, everything works as it should. Air conditioning and all electric cooking, both boats function in the Americas and Europe, and the battery banks return to 100% nearly every day mostly via a 450w solar array. The larger boat will soon have a 950w array, I live on these boats 10 months per year always in anchorages.

Would you like some help with yours? My advice: Keep things simple and stick with technology which can always be purchased at your next port of call should the need arise.... someday, you’ll be glad you did.

[Q Xopa]

Originally Posted by stormalong

It seems to me that you should choose the voltage based on where you will be using the boat most. It is only North and South America that 110 volts is used.

Since you plan to spend a lot of time in the Med and S. Pacific I suggest 240 volts. Any time you are in 110 volt land you could use a transformer. If you have an inverter aboard the only 110 volt accessory you really need is a battery charger and there are many dual voltage chargers available.

The one exception to that is if you plan to winter over in 110 land and plan to heat electrically. In that case you can find 50 amp power sources that can supply 240 volt 60 Hz quite common in the U.S. With a little power connector wiring (with careful attention to grounding) You can use your 240 Volt devices too. Most 50 Hz devices will run on 60 HZ.

Yes agreed.

Probably more where you are going to get your appliances from most. Which is probably the same.

[Q Xopa]

Originally Posted by Stu Jackson

There have been a series of discussions about how to work with these choices on this very forum in the electrical section.



Indeed, in all of the many boating forums I read regularly, THIS is the ONLY one where knowledgeable folks explain the options.


Rather than me or anyone else suggesting you do a search, here's what I recommend: Go to the electrical forum and read a few dozens pages in of thread titles. It will soon become apparent to you which ones you should read in detail.


There are many options for you, in installation, equipment and operation.


I think all those have been discussed relative recently. Many of the threads are from folks coming or going to & from the US to EU and address your questions [perhaps not specifically for new builds], but I believe by reading about what others have experienced will help you with yours.





I keep repeating when I read this gem: None of us was born an electrician. We ALL had to learn it.


Good luck, and all the best with your brand new boat, not too many get that opportunity.

Yes agreed plenty of good info given previously.

[Q Xopa]

Originally Posted by nwdiver

As noted above, it is easy to use 110 wiring for 240 not the other way around, most of the world is 240, have them install the wire gauged for 110 run 240 through it and if someone down the line want 110 it's an easy switch over.......if the wiring is not in place it's a pita....

Yes if it were me that was doing a new boat.

I would get the fatter 110v wiring.

I would probably do the Inverter 240v and appliances as thats what you can get easily locally. They are slightly more efficient too, but not really a consideration.

I would also have a 'universal' voltage and frequency charger.

Of course there are many ways people can and do handle these choices.

[jdtcanuck]

Another consideration - I was advised by a North America broker that 230V 50Hz boats are much more difficult to sell on the NA market and are usually discounted vs a similar 110V 60Hz model.

[Dockhead]

Originally Posted by jdtcanuck

Another consideration - I was advised by a North America broker that 230V 50Hz boats are much more difficult to sell on the NA market and are usually discounted vs a similar 110V 60Hz model.

That's a good point. And it's much cheaper and easier to convert a 110v to 230v than vice versa. UNLESS the manufacturer uses the same wiring for 230v boats. The OP might want to check on that.


If there's a concern about selling into North America, AND if the OP is going to have a separate generator set, then he might also want to check and be sure that the generator can be converted to 110v. Most heavy duty generators can.