charger power supply

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charger power supply

Postby quarry44 » Sun Oct 30, 2011 10:55 pm

I have recently converted a couple more computer power supplies to power my chargers.
I've got the usual 5 and 12 volt outlets,plus the common ground.
My query is,can I pair up the 12+ and 5+,or 12 +and 3.3 +,to charge a 12v lead acid gel cell(7.5Ah).Am I correct in thinking I need more than 12 v,as the fully charged 12v gel cell reads 14.4volts?
I do have a charger for the gel cells,but it has no meter or other method of checking the battery.Hence I appear to be overcharging or undercharging them .I would therefore like to use the Turnigy Accucel to charge them,using the computer power supply.This might be very basic electrickery for some,but I know just enough to be dangerous :mrgreen:
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Re: charger power supply

Postby ergocentric » Mon Oct 31, 2011 12:16 am

You want max. 14.4 Volts or you will cook the battery, you want a power supply with suitable internal resistance to limit the current to c/10
a smart charger is best
unconcerned but not indifferent - MAN RAY
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Re: charger power supply

Postby S-rob » Mon Oct 31, 2011 6:12 am

quarry44 wrote:My query is,can I pair up the 12+ and 5+,or 12 +and 3.3 +,

No , as they all have common ground /common -ve
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Re: charger power supply

Postby disco stu » Tue Nov 01, 2011 12:04 pm

Your 12v and 5v will give you 7v rather than 17v. The 5v is treated as the -ve. You can get a nice combination of voltages out of them
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