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Unread 28-01-2008, 07:20
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Al Skierkiewicz Al Skierkiewicz is offline
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AKA: Big Al WFFA 2005
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Re: Wiring the IR Receiver

Quote:
Originally Posted by RyanN View Post

Parallel circuits are completely different. The current changes, and the voltages should be an average of the energy sources (I have a 6V and a 12V battery, and put them in parallel [Bad idea by the way, don't do this] then the voltage should be around 9V.) As for the current, if you have 2 12V 17AH batteries put in parallel, it should make the output current 12V and 34AH.
Ryan,
Unfortunately this is not the case. The six volt battery voltage would rise slightly during the time the 12 volt battery would be able to supply it current. The 12 volt would continue to try and dump current until it fell to 6 volts as well. If both batteries were fully charged to begin with, all the excess current would be turned into heat likely destroying the batteries or at least causing some nasty venting.
In the case of the 12 volt batteries in parallel, one will always be slightly higher voltage than the other. This condition will cause current flow between each of them as they ping pong trying to deliver current to the lower voltage battery. Without diodes directing current flow, the two batteries, over time will deplete each other right down to zero volts.

Brent,
The way you hooked up the power will work until the backup battery falls below the 7 volt cutout on the regulator. At that point the regulator is no longer functioning and acts more like a resistor. It may work for a while but may not be reliable.
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Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
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Storming the Tower since 1996.

Last edited by Al Skierkiewicz : 28-01-2008 at 07:23.