battery wiring for 6 and 12 volts concurrently

[greg turekParticipant @gregturek35930]

[greg turekParticipant @gregturek35930]

Can one wire up 10 cells so at the same time 12 volts can be accessed as well as 6 volts (using all cells, ie in parallel) I have done it only by using a bank of 5 cells to provide 6volts and the 10 cells for 12volts. it doesnt seem possible to my ignorant electronic mind to do this, but perhaps someone knows better.

[Dave MilbournParticipant @davemilbourn48782]

Only by feeding the 12v into a linear voltage regulator or DC-DC converter.

DM

[Robin LeeParticipant @robinlee31938]

To get the 12 volt supply all 10 cells would be connected in series. If you want 6 volts as well you could tap off at the mid-point of the 10 cells. You would of course have a common return path to the negative end of the 10 cell stack. One aspect to be kept in mind is that the drain on the lower 5 cells would be the summation of the two loads (12volt and 6volt) whereas the upper 5 cells of the stack would only be supplying the current for the 12 volt load, in other words the lower 5 cells will discharge faster than the upper 5 cells. There might also be some problems associated with noise between the two loads. Personally I would be happier with two separate batteries but perhaps you could give more deatails of the loads you have in mind. For instance if the 6 volts was just for a small lighting circuit should be no problems.

[greg turekParticipant @gregturek35930]

Thanks Dave and Robin for the info. I suspected that there was no simple way of doing it just with wiring configuration. voltage regulation etc is way too complex for my purposes. The 10 cells are NiMh D cells and are used also for ballast in a Billings Calypso. So the 6V is for the 2 motors and the 12V is for lighting. Might be better to just wire the 10 cells for 6V and add another smaller 12V pack for lights, or abandon the idea of the D cells and just use 2 separate smaller packs and add some extra lead ballast.

[Dave MilbournParticipant @davemilbourn48782]

Greg

I’d go for the separate 12v pack. Unless you have a hundred lights or maybe 40W bulbs then the current drawn by the lighting circuit will be pretty low (<<1A) so you could use NiMH cells of AA size and still get nearly 3AH from them. If you use LEDs for lighting then the current will be even less.

BTW the P101 amplifier runs best from at least 12volts…….

Dave M

[Author]

Posts