I have the traditional two battery with the usual Off 1, 2, or All switch and each bank giving out 12 VDC. I would like to put some 24 VDC components aboard so would like to have 24VDC available when I want it. Is there a straight forward reliable way I can do this or should I just dump the idea completly?
24 volt electrics option.
- Thread starter colin hunter 335
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Inverter?
Hiya Colin, Not an electrician here, there are some knowledgable mates around here though and they will likely post (if only for me to look stupid, that isn't much effort) Why 24 volts? You can do it, a switch to put the banks in series, but why do that. A good inverter is great to have, then you have 110 AC with a small sacrificial drop, worth the effort though.
Hiya Colin, Not an electrician here, there are some knowledgable mates around here though and they will likely post (if only for me to look stupid, that isn't much effort) Why 24 volts? You can do it, a switch to put the banks in series, but why do that. A good inverter is great to have, then you have 110 AC with a small sacrificial drop, worth the effort though.
wave of the future??
Seems like a lot of mfgs of boats as well as cars are seriously considering the same thing to deal with the multitude of electrical demands of our electronic toys. Some large power boat mfgs are currently running on mostly 24VDC now. You may just be a little ahead of your time Colin. As long as you can isolate the circuitry from the 12VDc system, just get some hefty 12V batteries , connect them in series and your there.
Seems like a lot of mfgs of boats as well as cars are seriously considering the same thing to deal with the multitude of electrical demands of our electronic toys. Some large power boat mfgs are currently running on mostly 24VDC now. You may just be a little ahead of your time Colin. As long as you can isolate the circuitry from the 12VDc system, just get some hefty 12V batteries , connect them in series and your there.
3 choices
1) drop the idea and go with 12 Volt devices 2) add two 12 Volt batteries on a seperate electrical grid and connect them (pos to neg) to make 24 volts 3) go with an inverter from 110 to 24. Problem with #1 is you don't get what you want. Problem with #2 is the additional weight and space the two additional batteries take up as well as having to run new wiring. Problem with #3 is it only works when you have 110 volts and you loose some electricity (usually not that big of a deal when you have 110 volts). You only have 110 when at the dock unless you have a generator and generators are loud, heavy and expensive. Pick your poison.
1) drop the idea and go with 12 Volt devices 2) add two 12 Volt batteries on a seperate electrical grid and connect them (pos to neg) to make 24 volts 3) go with an inverter from 110 to 24. Problem with #1 is you don't get what you want. Problem with #2 is the additional weight and space the two additional batteries take up as well as having to run new wiring. Problem with #3 is it only works when you have 110 volts and you loose some electricity (usually not that big of a deal when you have 110 volts). You only have 110 when at the dock unless you have a generator and generators are loud, heavy and expensive. Pick your poison.
Think of it the other way round
You don't want a 12 volt boat with an additional 24 volt system, you want a 24 volt boat that you tap off 12 volts on the low side battery. Most electronics have a 11-32volt range so you might only have to buy new lghts. The starter will do OK if you don't grind it much. With the higher voltage you will get a REALLY good crank speed! Same story for anything with motors. Before you say it, they run at a higher RPM and draw around half the current. The alternator will have to by reregulated, most can put out 50 volts if they are full fielded so just a new regulator. For those items that can't handle 24 volts you can run a circut from the low side 12 volt battery + to the fuse to the device and back to that same battery's neg terminal. By low side I mean two batteries in series. One has a 24 volt + term and a 12 volt - term, the other has a 12 volt + term and a 0 volts - term. The low side is the 12 + and 0 - battery. We used to use a series 24 volt connection to jump start car diesels in cold weather. Just don't turn on the ignition and burn out the idiot lights. OBTW when you go to 24 volts you half you battery bank AH capacity!!!! Course you half your amp consumption too!!
You don't want a 12 volt boat with an additional 24 volt system, you want a 24 volt boat that you tap off 12 volts on the low side battery. Most electronics have a 11-32volt range so you might only have to buy new lghts. The starter will do OK if you don't grind it much. With the higher voltage you will get a REALLY good crank speed! Same story for anything with motors. Before you say it, they run at a higher RPM and draw around half the current. The alternator will have to by reregulated, most can put out 50 volts if they are full fielded so just a new regulator. For those items that can't handle 24 volts you can run a circut from the low side 12 volt battery + to the fuse to the device and back to that same battery's neg terminal. By low side I mean two batteries in series. One has a 24 volt + term and a 12 volt - term, the other has a 12 volt + term and a 0 volts - term. The low side is the 12 + and 0 - battery. We used to use a series 24 volt connection to jump start car diesels in cold weather. Just don't turn on the ignition and burn out the idiot lights. OBTW when you go to 24 volts you half you battery bank AH capacity!!!! Course you half your amp consumption too!!
You May Want to Research a Little More
You may have trouble charging your batteries evenly if you tap 1 battery for 12 volts where you have two batteries in series for 24 volts. I have a 24 volt diesel Landcruiser and if I draw 12 volts off one battery for the radio the alternator overcharges the full battery while it attempts to bring the tapped battery up to full charge. Perhaps there is a smart charging system to charge 12v batteries seperately using a 24v alternator output but I am not familar with it. If you find a way that works let us know!
You may have trouble charging your batteries evenly if you tap 1 battery for 12 volts where you have two batteries in series for 24 volts. I have a 24 volt diesel Landcruiser and if I draw 12 volts off one battery for the radio the alternator overcharges the full battery while it attempts to bring the tapped battery up to full charge. Perhaps there is a smart charging system to charge 12v batteries seperately using a 24v alternator output but I am not familar with it. If you find a way that works let us know!
interesting idea
I would be inclined to have separate circuits for each 12/24/120. Tapping off the low side of a 24VDC circuit to get 12V dosen't sound like a good plan to me nor does running 12 volt devices at 24VDC routinely. The new smart chargers may well be able to handle multiple voltages and seperate banks. What do you intend to power?
I would be inclined to have separate circuits for each 12/24/120. Tapping off the low side of a 24VDC circuit to get 12V dosen't sound like a good plan to me nor does running 12 volt devices at 24VDC routinely. The new smart chargers may well be able to handle multiple voltages and seperate banks. What do you intend to power?
Lest we get the wrong idea
My assumption (yes, it is true again) was that there would be only a small number of items that would need to be run on 12 volts as he wants to convert (as much as possable) to 24. Lowell is correct about charging, it is an issue but the amount of current a radio draws is, IMHO not going to KILL a battery. Lowell has facts and I have opinions here, you decide. The running of motors on x2 voltage is only an issue if you stall then. They then draw twice the current and the ABYC "shall operate while stalled for 6 hours with out catching fire" rule is probably not going to be valid anymore. I am just trying to give some way forward and not trying to be the project electrical engineer. You makes your choices and you takes your chances.
My assumption (yes, it is true again) was that there would be only a small number of items that would need to be run on 12 volts as he wants to convert (as much as possable) to 24. Lowell is correct about charging, it is an issue but the amount of current a radio draws is, IMHO not going to KILL a battery. Lowell has facts and I have opinions here, you decide. The running of motors on x2 voltage is only an issue if you stall then. They then draw twice the current and the ABYC "shall operate while stalled for 6 hours with out catching fire" rule is probably not going to be valid anymore. I am just trying to give some way forward and not trying to be the project electrical engineer. You makes your choices and you takes your chances.
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