johnskit
New member
What are the pro's and con's of a 24V system as compared to the more common 12V for domestics and engine starting?
Your thoughts please.
Your thoughts please.
24V vs. 12V
- Thread starter johnskit
- Start date
G
Guest
Guest
24v - cheaper (thinner) cable, voltage drop less of a problem, need at least 2 batteries so you can wire in series, can be difficult to find compatible equipment. 12v - reverse of the above!
ps. wish my boat was 24v!
ps. wish my boat was 24v!
VMALLOWS
New member
Not much. Just that the voltage-drop to devices will be less on 24v (because the current will be halved), or alternatively, the wiring can be thinner.
On the negative side, 24v devices are very much less common - especially when looking for engine bits, light bulbs, etc. (though a lot of modern electronics will cope with both).
On the negative side, 24v devices are very much less common - especially when looking for engine bits, light bulbs, etc. (though a lot of modern electronics will cope with both).
HaraldS
New member
As was said, half the Amps and half the necessary cable sizes, still not dangerous, but feelable with wet fingers.
Biggest advantage with big consumers, like anchor windlasses, bow thrusters, power winches etc. Motors can be smaller at same power, alternators too.
On the down side you'll need to have a DC-DC converter for providing 12V to many a 12V equipment. Losses are not a big issue in that case and with good converters you get galvanic separation as an extra bonus which is nice for noice elimination on radios and preventing galvanic corrosion.
Biggest advantage with big consumers, like anchor windlasses, bow thrusters, power winches etc. Motors can be smaller at same power, alternators too.
On the down side you'll need to have a DC-DC converter for providing 12V to many a 12V equipment. Losses are not a big issue in that case and with good converters you get galvanic separation as an extra bonus which is nice for noice elimination on radios and preventing galvanic corrosion.
tyger
New member
Re: I concur...
...with the postings below.
My last boat, a 45 foot motor junk used as a live aboard, had 24 volt electrics.
A big advantage was the ease with which the engine (a 165hp Perkins) started - even when the batteries were low.
In my part of the world 24 volts is commonly used on fishing boats so a lot of equipment and spare parts can be purchased at commercial prices rather than yachty prices.
I think 24 volts is worth considering on any boat over 40 feet.
24 volt equipment seems more common in the UK than the USA although I've found that American manufacturers will supply 24v equipment on request.
The Americans also use 32v on larger boats, now there's complicated...
...with the postings below.
My last boat, a 45 foot motor junk used as a live aboard, had 24 volt electrics.
A big advantage was the ease with which the engine (a 165hp Perkins) started - even when the batteries were low.
In my part of the world 24 volts is commonly used on fishing boats so a lot of equipment and spare parts can be purchased at commercial prices rather than yachty prices.
I think 24 volts is worth considering on any boat over 40 feet.
24 volt equipment seems more common in the UK than the USA although I've found that American manufacturers will supply 24v equipment on request.
The Americans also use 32v on larger boats, now there's complicated...
gunnarsilins
New member
I got 24 V on...
...my Moody 42. So I have some experience and can compare with my previous yachts, which all had 12 V.
Pros:
*Less voltage drop.
*Easy engine starting when cold
Cons:
*Most electronic equipment runs on 12 V - I have not less than 4 converters to cope with this
*Less equipment which should or can not be run on a converter to choose between: - various pumps, chargers, heaters, vacuum cleaners, light appliances with halogen bulbs etc.
*Batteries need to be in series - takes up space
*If solar panels are an issue, then they need to be doubled
*If you run in to trouble with the starter or alternator not all workshops are able to help, at least getting spares might take some time - or you should try to find somebody dealing with lorries and trucks
I must say, despite the fact that I have a big yacht with considerable electric demands I would opt for a 12 V system if I could choose, because in the end a 24 V system is much more expensive to install and maintain.
But if the cost is not an issue - then I beleive a 24 V system is a much more 'proper' choice.
...my Moody 42. So I have some experience and can compare with my previous yachts, which all had 12 V.
Pros:
*Less voltage drop.
*Easy engine starting when cold
Cons:
*Most electronic equipment runs on 12 V - I have not less than 4 converters to cope with this
*Less equipment which should or can not be run on a converter to choose between: - various pumps, chargers, heaters, vacuum cleaners, light appliances with halogen bulbs etc.
*Batteries need to be in series - takes up space
*If solar panels are an issue, then they need to be doubled
*If you run in to trouble with the starter or alternator not all workshops are able to help, at least getting spares might take some time - or you should try to find somebody dealing with lorries and trucks
I must say, despite the fact that I have a big yacht with considerable electric demands I would opt for a 12 V system if I could choose, because in the end a 24 V system is much more expensive to install and maintain.
But if the cost is not an issue - then I beleive a 24 V system is a much more 'proper' choice.
LadyInBed
Well-known member
My boat came equipped with both 12 and 24v systems. 24 for the high drain devices - anchor winch, fridge and electric toilet, the rest on 12v.
This makes for complications, as the engine has to drive two alternators. The 24v wind gen has a second regulator to convert and charge the 12v system, and I have three banks of batteries, two 12 (engine and domestic) and a 24.
I suppose the good thing is that I should always have a battery to start the engine!
This makes for complications, as the engine has to drive two alternators. The 24v wind gen has a second regulator to convert and charge the 12v system, and I have three banks of batteries, two 12 (engine and domestic) and a 24.
I suppose the good thing is that I should always have a battery to start the engine!
johnskit
New member
Many thanks for all your contributions. My apologies for not acknowledging your answers before now. I was out sailing! Bit windy in the eastern Solent yesterday afternoon!
