12v - 24v question?
#1
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I have used a 24v system on my old boat for the trolling motor but it was a stand alone system. On the new boat I have 2 batteries and they are wired so everything is 12v. I just got a Rule 3700 gph pump for next to nothing, but it's 24v. This will be the backup/emergency pump and I wouldn't mind it being 24v. My question is can I rig this pump up to the batteries in a way that will give it 24v without making the whole system 24v? The way I did it on the trolling motors was just connect the + to the - on the batteries with another battery cable. Then wired off the oposite + and - terminals. But that would fry the rest of my stuff. Or should I just sell the pump and get a 12v? ;?
#3
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Agree with jtburf above. 24v appliances belong on boats that are running 24v and not on a boat that, oh yes has a 24v set up. What you got for next to nothing could end up costing you a bunch in the long run.

#4
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Yeah thats what I thought. I ended up putting it on Ebay and the trading board. So much for me getting a deal

#5
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There is an efficiency to running the 24v system but at the expense of adding a converter. One way is maintain your 2 12v batteries in parallel for charging purposes and have a 12v feed into a DC/DC converter which will yield both a 24v and a 12v output. Unfortunately the converter will set you back a few hundred bucks.
cat
cat
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Catmandu, I think you may have told me this before, but what converter are you using?
I'm told that I can have two batteries grouped for 24v and still have them parallel for 12v. They would be charged as 12v batteries. I want to verify this before "just trying it". This would not require a converter.
I'm told that I can have two batteries grouped for 24v and still have them parallel for 12v. They would be charged as 12v batteries. I want to verify this before "just trying it". This would not require a converter.
#7
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buck-you can have 2 batt in series for 24 volts, and use each of those batts indivly as 12 volt if you need to. you can charge each of the 24 volt batteries seperately as long as you put + and - on each 12 volt batt and not on the + of batt 1 and - on batt 2. i have my trolling motor hooked up as 24 volts, and i have my radio/amp hooked up to 1 of those batteries as well. i use a dual pro charger to charge all my batteries no problem.
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Could I also have them in parallel of one another? I want to run all my 12v items of these two house batteries also and would prefer not to have all the juice pulled off only one battery. I will charge them as two 12v's.
Thanks for the help!
Thanks for the help!
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yea 10-4, you can hook up misc 12 v items to those batts, make sure to hook up the + and - to same batt, if want a 24 v application ,hook up + on batt 1 and - on batt 2. you need to run a series wire from + batt 1 to - batt 2-your all set. make sure that if you run a radio and amp- install both to same batt, they run together- i tried separating them and my install guy said i was lucky i did blow it up. get a volt meter and check voltage to make sure all is set properly. the way it was explained to me is that even though you run a series wire to make both batt 24 volts, the only way to get those 24 volts is to go + batt 1 and - batt 2. if you keep your + and - on batt 1 for example you will be only drawing 12 volts and so on.
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Buck Wild
hi,
I think we did have dialogue some time ago. Anyway, the DC/DC converter I use is from majorpower.com (model MajorVTC305-12-24). There are other choices but I needed a minimum of 7.5 continuous amps. You can hook up 2 12v batteries in series as suggested and have an AC charger at the dock but I need continuous recharging on the water (12kw radar). I have 4 batteries on board...one for cranking to each OB and a house bank of 2 which feed to the converter- all are in parallel and are charged when low voltage is sensed. Then I have a 24v line from the converter to the Navnet and the remainder of the electronics are fed from a 12v line off the converter.
cat
hi,
I think we did have dialogue some time ago. Anyway, the DC/DC converter I use is from majorpower.com (model MajorVTC305-12-24). There are other choices but I needed a minimum of 7.5 continuous amps. You can hook up 2 12v batteries in series as suggested and have an AC charger at the dock but I need continuous recharging on the water (12kw radar). I have 4 batteries on board...one for cranking to each OB and a house bank of 2 which feed to the converter- all are in parallel and are charged when low voltage is sensed. Then I have a 24v line from the converter to the Navnet and the remainder of the electronics are fed from a 12v line off the converter.
cat