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Old 07-18-2012, 05:20 PM
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Default battery swapper

Hi everyone

Help==not electronics schooled but I build projects--big learning curve!!!
To begin with--thanks in andvance for assistance.

I have several questions

First question:

I have two batteries--one hooked up to a circuit-(bat 1) and a
spare-(bat 2).

When bat 1 drops below a certain voltage ( I would like to be able to set this voltage)--I would like to automatically disconnect bat 1 from the circuit and have bat 2 replace it to continue driving the circuit.

Would I use a zener and a relay or ????--no idea were to start.

More questions to follow

Thanks P_E_T_E_R
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Old 07-18-2012, 05:24 PM
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BMorse BMorse is offline
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you can get voltage detectors with preset triggering levels to switch between the batteries...... and you can also use one to switch back to battery #1 once battery #2 gets to a certain level.... that's if you already replaced battery #1 or the circuit would end up oscillating between the 2 batteries..... or include a comparator circuit to monitor the voltage level to switch between batteries....

What size batteries and what voltage????
There is no spoon -Neo-
Disclaimer: The example programs,circuits, projects and information I provide or post on this web site are for educational purposes only. By copying anything from this site posted by me, you agree to the "as is" nature of the programs, circuits, information and to the statements listed in this disclaimer.No warranty or liability is expressed or implied. Working with AC /DC voltages can be dangerous and even deadly. Proceed at your own risk!

Last edited by BMorse; 07-18-2012 at 05:31 PM.
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Old 07-18-2012, 06:16 PM
wayneh wayneh is online now
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Boaters do this routinely but usually want to manually choose which battery is being drawn down. I believe it's common to use a "starting" battery for starting the motors and a deep cycle battery for lights and radio when the engine is not running.

Anyway, why do you want to switch instead of just using two batteries in parallel? They'll both last longer.
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Old 07-20-2012, 03:39 PM
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Hi BMorse and wayneh:

Thanks for your comments. I try to supply relavent info so you can better understand whats up.

I would like to build my own circuits--I don't want to buy some kit unless of coarse it makes more sense to do so.

What I want to do is build a motor--(similar to a John Bedini SSG)
but with some of my own ideas.

I have an idea of the way I want to go and in order to not get over whelmed, I thought I would work on one circuit at a time so that I could understand what's going on--(not being an electronics dude).


--build a circuit to monitor the voltage level of each independant storage battery--(12 volt)--(sealed lead acid---7.2, 12 and 32 ah are the sizes I will be using--not together).
--if battery drops below a level--(selectable in range--say 12.2v as an example) --to disconnect it from the circuit.
--to be able to direct this battery to be recharged or--have the ability to redirect the voltage to be used as required



--build a circuit to monitor and control the voltage level of independant Storage Capacitors
--also on a 12 to 24 volt system.
--as the capacitor charges I want to be able to direct the output to power a coil or direct it to a storage battery.

Basically what I want to build is a capactive discharge motor and to be able to control and set all voltage levels.

I hope this is a little clearer of what I am attempting to do.

I have already built the motor---these are some things I'd like to do to have better control.

Once again I appreciate any assistance

Thanks P_E_T_E_R
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Old 07-20-2012, 04:24 PM
wayneh wayneh is online now
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Uh oh, you're not pursuing "free energy" are you? Impossible.
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