electic kW / diesel kW

Mydauphin, we are talking about different animals here.
The panel I sold and still use are Siemens, aluminum frame, Corning tempered glass. Laid up on both ends a man can stand in the middle and jump: no damage. Mounting is done with a rubber grommet and a stainless bolt.

The panels you have must have come cheap, you do not need 48 volts.
I would not buy anything but make a switch mode down converter. Most of the parts you need are in any computer supply and these cost almost nothing nowadays. If you don't want to make anything, buy 3 small PC supplies, wire both the panels in series for 96 volts and the 5 volts outputs to get 14V to charge your batteries (adjust the +5V just a little bit).

Is that cheap or isn't it?

 

Interesting Idea. But what 3 step charging...

 

I also don't understand PC power supply idea. It is very intriguing especially since I have a bunch of them. The panels produce 48 Vdc, I put in series and they put out 96 vdc. So far so good. But Pc power supply is expecting 110 vac, therefore it has transformer, wont work with Dc, to reduce voltage, then diodes or something like it to convert to DC. I am sure you know what you are talking about but I don't see anything here to reduce 96vdc to 14vdc. My solar Bp 180 Watt solar panels were State of the Art 5 years ago, did get them for free when a hurricane blow them off a top of a building unto my house.

 

The PC power supply is a switch mode device. It has no primary transformer and accepts both AC and DC. It also compensates for the lower input voltage of the PV panels.

 

Really!!!. Ok so I rig 2 PS in parallel feed then 96 volts and it is going to convert them to 12vdc and 5vdc. I know i got something wrong

 

yeah if that's correct its pretty sweet - esp. if efficiencies are not terrible

 

These supplies make 5vdc, precisely stabilized, very efficient and able to handle heavy loads. The other voltages are byproducts with much lower currents.

A minimum load must be present to start the circuit, so if you do the experiment and there is no output voltage you might think I fooled you.
A small light bulb (12v, 10 or 15 watts) is enough. When used as a battery charger you do not need it of course.

There is a small trimming pot on the circuit board to adjust the 5vdc output. If you can turn that up to 7 volts you need only two power supplies to charge 12V batteries.