24volt systems advantages and disadvantages

[kunyang]

We're looking at a yacht to buy and it has a 24v system on board. Is this a problem. Is it easy to get Raymarine or BG etc instruments, etc. What are the thoughts / experiences.

Thanks Dave

 

[prv]

A lot of modern electronics - but not all of them - quote an input voltage of something like 9 to 32 volts and will be perfectly happy on a 24v supply. It's quite common to have a 12v circuit as well though, for the 12v-only stuff. This can either be taken off half the battery bank (not ideal for health of the batteries, but cheap) or supplied via a converter box. You would want the heavy (windlass, thruster if any, winches likewise) and medium power users (autopilot, fridge compressor) to be 24v versions.

Pete

 

[David2452]

No problems with any modern kit (VHF aside in many cases) other advantages are easier use of lighter cable or lower volt drop for the same cable, I have never had an issue sourcing any electrical items such as pumps, bulbs including LEDs etc and cost is no different, I work on quite a lot of 24v systems but mostly on larger vessels and quite like it, especially the big 60w ES bulbs in a wide choice of light fittings

 

[Colin K]

Hello,
We have a Kingfisher 30 which is 24 v most of the goodies ran as said no problem as their voltage range was wide. Always nice to have 12v of course as the standard chargers are 12v. And A couple of bits were only 12v so we had a 12v battery with a small fuse panel. We had a 24/12 v reducer that charged the 12v bank fine.
24 v is half the draw so we ran a fridge/24v Eber and all manner of amp thirsty goodies without problem.

All the best, Colin.

 

[William_H]

Yes I would think it a definite plus having a 24v system. Starter winches thrusters inverters heaters etc all use so much power that 24v is far better. Less volt drop in wiring due to current being only half for the same power. But also any small volt drop is less part of the starting 24v so less significant again.
You can get voltage converters for 24 to 13.75 volts if you really need 12v nominal for any gear.
Does the boat have a dual 24v system if so this gives you redundancy for engine starting? If not an ideal system might have the 24v for the engine which via a VSR feeds a 24 to 13.65 v converter to a 12v battery for domestic services. Hence no concern about flattening the 24v battery when anchored. An even better system would have 2x 12v batteries in parallel for domestic. An arrangement of jumper leads or switches could then be used to put these in series for 24v engine jump start if and when engine batteries get old. good luck with the purchase olewill

 

[grumpygit]

Yes I would think it a definite plus having a 24v system. Starter winches thrusters inverters heaters etc all use so much power that 24v is far better. Less volt drop in wiring due to current being only half for the same power. But also any small volt drop is less part of the starting 24v so less significant again.
You can get voltage converters for 24 to 13.75 volts if you really need 12v nominal for any gear.
Does the boat have a dual 24v system if so this gives you redundancy for engine starting? If not an ideal system might have the 24v for the engine which via a VSR feeds a 24 to 13.65 v converter to a 12v battery for domestic services. Hence no concern about flattening the 24v battery when anchored. An even better system would have 2x 12v batteries in parallel for domestic. An arrangement of jumper leads or switches could then be used to put these in series for 24v engine jump start if and when engine batteries get old. good luck with the purchase olewill

+1 Better all together as WH has explained.
We are 24v and very pleased we are and equipment is the same price or around the same as 12v, e.g. pumps, windless, navtronics etc. With the electonics you'll find most manufactures have a voltage range of 10v to 32v and such as Standard Horizon is up to 35v. If not as said there's the voltage converters.
Our domestic battery banks are made up of 4 x 6v in series for the 1st and the 2nd bank is 4 x12v of which 2 pairs are in parallel then the 2 sets of pairs series up to = 24v. Solar panels are 2 x 12v in series and 2 x 24v in parallel. So as you can see, plenty of combo options.
You don't say what boat it is but it will most probably all kitted out with your needs.