[Elecraft] Who sells a small RF quiet solar charge controller?

[Jim Brown]

There's a serious misconception here too -- the maximum voltage that the 
controller will handle depends on the design of THAT particular model.  
SOME MPPT controllers are designed for a max voltage of 24V, others for 
48, and so on. Ditto for current ratings -- the relevant spec is the max 
short-circuit DC output of the panel(s).  Genesun, the mfr whose MPPT 
controllers I recommend, has several models for different voltage 
ranges, at least as high as 24V battery voltage, and maybe high as 48V. 
Last I looked, their biggest model was rated for 10A.

73, Jim K9YC

On Sun,3/19/2017 12:15 PM, Paula Keezer wrote:
> I have seen some misconceptions about MPPT.  The best reason to use MPPT is
> so that you can put multiple solar panels in series and you will not exceed
> the maximum input voltage of the controller.  The controller will continue
> to charge even in partial sunlight just as long as the input voltage exceeds
> the battery charge voltage (in this case 14.xx volts).  Since solar panels
> in series ADD voltage, with two solar panels you get a  24 volts (well, more
> like 32 volts in full sunlight) and when those panels are in shade, the
> individual panels may drop down below 12 volts but the sum of the two will
> be much higher than the required charging voltage.