battery backup system

ideaman234

I am trying to make a battery backup circuit to connect to my project. Normally the circuit would be attached to a 12V adapter, but during an outage i want to be able to automatically switch to a wet cell 12V battery and automaticallky recharge it. any ideas or circuits i could make?

Tom Walker

The battery backup and switchover part of this is relatively easy. The recharging can be frought with peril. Both cases are thoroughly covered elsewhere in this forum.

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Franklin

Hook your battery to a charger and plug it in. Run your circuit from the battery terminals. If the charger is sized correctly (Trickle charge) the battery will keep the charger from over powering the circuit.

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- Stephen

Chris Savage

Please see the following thread as this has been covered a few times before, and there is a link to the datasheet for the part you need.· I hope this helps.

http://forums.parallax.com/showthread.php?p=556910

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Chris Savage
Parallax Tech Support
csavage@parallax.com

Jim Richey

I have been using simple float chargers,available from Harbor Freight,on several 12V batteries to keep them topped off.They consist of a wall transformer and circuitry to prevent overcharging.Never any problems with them and they only cost $5.00 each (on sale).

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