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6 volt and 12 volt combination

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6 volt and 12 volt combination


Post by 51Hog » Wed Apr 27, 2005 6:02 pm

I have found a 6 volt battery at NAPA auto--6n6-3b
Info is here ... or_con.asp

The question I have is this:

I want to run a 12 volt security system on a 6 volt bike.
Can I connect two 6 v batteries in series to get 12 volts for the alarm and still charge as a 6v battery--and still run bike as a 6v system from the same two batteries by hooking to the + and - terminals from the same batt?

I am thinking that I should be able to pull 6v from the + and - from one battery for the 6v system.

and pull 12 v from the + on one batt and the - on the other---with the other + and - connected together.

Will the 6 volt genset still charge both batteries?
What am I not seeing??

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Re: 6 volt and 12 volt combination


Post by Sidecar » Wed Apr 27, 2005 7:51 pm

You can not hook the two batteries in series and charge them at the same time. Draw it on a piece of paper and you will see that you can't do it.
It's rather hard to explain in words.

You could charge them in parallel and change to series for the alarm, after you shut the bike off, but it's gonna be a pain in the arse.

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Re: 6 volt and 12 volt combination


Post by Red55FL » Wed Apr 27, 2005 11:35 pm

If you have found the room to install another 6-volt battery, why not buy a small sealed 12-volt battery to power the security system and mount it where you were going to put the second 6-volt battery. Charge the 12-volt at home with a trickle charger. Security systems don't draw much power until they are triggered, so they don't need much power.
The other option is to buy a 6-volt to 12-volt step up transformer to power the security system from your existing 6-volt battery and mount it in the same place you found to mount the extra 6-volt battery. This is probably the best way to go as you won't have to worry with charging another battery.
I am not an electrician, so I can't tell you what to get or how to hook it up, but I work with electricians and electronic techs all of the time. They set power up and down for what ever it is I want to power. Find an electrical supply house & they can tell you what you need and how to do it.


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Re: 6 volt and 12 volt combination


Post by awander » Sun Aug 07, 2011 6:54 am

You can't use a transformer for DC-transformers work on AC only.

It would be possible to build a circuit that would generate 12VDC from 6VDC, but it would be impractical to do in this case. As Red suggested, use a small 12V battery, trickle-charged when you are at home, for the alarm system.

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Re: 6 volt and 12 volt combination


Post by 58flh » Sun Jan 20, 2013 12:59 pm

What about a GUEST-Circuit like on my boat!--I had 2-12V batts. & would run the nightlights while anchored & fishing ,Then start motor & simply flip the switch to the #2batt & let it charge!-(this was by ALTERNATOR!)---I know it would probably tax a Genny pretty hard!--,But As long as the Alarm isnt singing all night It should use no VOLTAGE!-(I doubt that the Flashing L.E.D.)-will use any VOLTAGE in 8hrs.! Just my 2 on it!-(by using the guest-Batt. tender It can be hidden in the toolbox with room to spare!)-& you will Always have a Hot-6V batt. to ride!.--You can wire for seperate-use,Batt.#1,& Batt.#2, both will be at 6V--But position 3 should give you 12V as it puts the 2-Batt. in series!,Just remember to switch-it back when heading out!---Look into it in MARINE SUPPLY-ELECTRICAL!---RICHIE

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