[Power] Charge controller ?

[Mikus Grinbergs]

>> Assuming the intent is to have a 12 V battery supplying power to two XOs
>> at a time, any recommendations on "charge controller" __specifications__
>> for that kind of a setup ?
> 
> The answers to such questions always depend on what you want to do with 
> the system. Supplying power to 2 XO's can mean you want to fully 
> recharge the XO's from empty or it can mean that you just want to run 
> the XOs without using much of the XO's battery.

I had hoped for a guideline to a system "good enough" for practical use.

Putting the above advice into a calculation (the XOs being connected to
a large external battery):  8 watts * 2 XOs * 6 hours_used_per_day = 96
watt-hours required each day to keep those XOs running (discounting
losses).  Suppose the solar panels are rated at 24 watts (96 / 24 = 4
hours of charging needed per day) -- let's say the controller is rated
for 10 amps.  Is that a reasonable capacity for the controller ?

mikus



p.s.
> Next question is how 
> long do you want to be able to go without recharging from the sun?

I thought how long the XOs could keep going without recharging from the
sun depended upon the size of the external battery - not upon the rated
capacity of the charge controller.