pflaming Posted March 31, 2013 Report Share Posted March 31, 2013 (edited) Visiting with a car friend, he said one could connect two six volt batteries together in this fashion. (1) Battery A has the positive to ground and the negative to the starter post -- (2) Battery B Connect the two negative poles together and the two positive poles likewise. From Battery A run the standard six volt harness. Connect the positive post of Battery B to a fusebank. From that fusebank run 12 volt appliances: radio, radiator fan, etc. Anyone have experience with such? Edit: Tinkering like this does not appeal to me yet it is interesting to learn about the many ways things can be accomplished in the mechanical arena. Dad had a 1945 Model D John Deere tractor, it had two batteries for the starter and the lights. I always thought that was a 12 volt system, apparently it was (is) not. Edited March 31, 2013 by pflaming Quote Link to comment Share on other sites More sharing options...
Looznutz Posted March 31, 2013 Report Share Posted March 31, 2013 Yes is called in series circuit. We use this system in buses to run 12 and 24 volts systems. We use 4 batteries 2 for 12 and 2 for 24 volts. Quote Link to comment Share on other sites More sharing options...
55 Fargo Posted March 31, 2013 Report Share Posted March 31, 2013 For low amperage draw applicance such as a car stereo, plug in for Iphone, gps, you could get a power invertor from 6+ to 12-, and be done with it. What are you trying to create? If you need a pusher rad fan, and many other 12 volt -grnd items, maybe you need to convert to 12 volts-grnd. Besides this electric rad fan idea, what exactly do you need to the 12 volt power for, a car stereo only? Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted March 31, 2013 Report Share Posted March 31, 2013 You can also run a 6 volt positive ground system and a 12 volt negative ground system on the same vehicle. This will require 2 batteries and 2 charging systems. This has been done before. Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted March 31, 2013 Report Share Posted March 31, 2013 The way you discribe the battery connections, Neg-Neg and Pos-Pos, you have a parallel connection and it will still be 6 volts with more available amperage. To get 12 volts you need a series connection. One battery's Positive post connects to the other battery's Negative post. Then the remaining Neg & Pos posts will give you 12 volts. Yet if you tap off of only one battery you still have 6 volts. However, I strongly caution against this arrangement as the battery loads will be different. The battery that you are NOT tapping off half voltage will fail quicker than the other one because the charging will have to keep up with the higher load battery and the other one will get overcharged. This is not theory. I've seen it happen many times trying to power a 12 volt radio off of a 24 volt system by taping off of one battery. Merle Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted March 31, 2013 Report Share Posted March 31, 2013 + to + and - to - is parallel and as Merle says only doubles your available current and voltage stays the same series is + to - for how many batteries you have, adding the voltage of said batteries for total volts available lot of diesel tractors use the the twin 6 batteries with a center tap, single 12 volt dynamo for recharge. Tap the series batteries for dual voltage..while this will work etc the rotation of the batteries is required as I understand to given them long life over their use..many have adapted this to their cars for the use of modern accessories Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.