On Monday, December 31, 2012 8:18:40 PM UTC-8, Eric Greenwell wrote:
On 12/31/2012 7:31 PM, Dan G wrote:

Eric,

What diode would you use for the 2 contollers/1 pV option you use ?

My Solar panel is rated at 20W od 1.3A max.

Dan G



I'd just go to Radio Shack and get ones rated at 2 amps or more forward

current. They will all have enough voltage rating.



--

Eric Greenwell - Washington State, USA (change ".netto" to ".us" to

email me)

There is a slight benefit in using a Schottky diode in this application for their lower forward voltage drop. For the one controller sceanario this is more important as it affects the charge set point of the controller. But it also helps the other scenario as well. e.g. http://www.amazon.com/30pcs-1N5822-S.../dp/B007AU0GJI. I would not go to too lower diode forward current rating due to current derating (maybe 50%?) at temperatures they might happen in a charger environment/hot trailer.

I hope there is not a too high expectation about how fast a "20W" panel will charge these two batteries. Solar insolation on a flat non-tracking panel gets pretty low.

Darryl