First, never pull a load from one battery in a series configuration. This
will damage the one battery that is supplying the current to the load 12V
load. At 10Amps, any thing short of a switching converter will require a
heatsink larger than the batteries. A simple 50% duty cycle will not work at
these currents and the output inductor and capacitors will be huge. You
require a converter that has been designed for this purpose. That works at
high frequencies to minimize the Inductor and caps.

Contact:
Translectric Inc. 1-800-333-2589
ask the salesman for a SM2412-10 about $89.93 list
This unit is 85-90 % efficient with a load regulation of 200 mv
and less than 25 mv ripple. This unit is a computer quality power
supply with special filtering on the input. The output current
is guaranteed at better than 10 Amps. The Input is from
18 Vdc - 55 Vdc. This is a Industrial unit, that meet military specs.



Gordon Varney


> > I have a pair of 12 volt batteries wired in series for 24 volts.  In
> > addition to running 24 volt motors, I want to run around 10 amps worth
of 12
> > volt devices.

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