Solar trickle charge

[mike28]

I need advice on what I need to purchase to maintain my batteries by solar power. I have two Interstate deep cycle batteries in a parallel configuration. I only need to keep batteries up while in storage. I have contacted several sources with differing suggestions on wattage.

[lsbrodsky]

AM Solar seems to have their act together and should be able to help you. Or, PM Lewster.
Larry

[Mike91208]

This worked great for keeping the batteries topped off. (I've since sold it as I installed three solar panels on the roof.)
Amazon.com: BatteryMINDer Solar Charging System - 12 Volt, 15 Watt Panel, Model# SCC-015: Automotive

[drboyd]

A hundred and eighty bucks is a pretty high ticket for a 15 watt panel and a charge controller. You'd have to have a lot of blinky-lights on it to convince me it was a good deal.

This one is cheaper with more power - I have no knowledge or interest other than it popped up on eBay: High Efficiency 30W Mono Crystalline Solar Panel Charger Kit for 12V Battery | eBay

[Silver Hawk]

I bought two 15w panels at Harbor Freight 5 years ago for my trailers - cheep and still working great! Did not come with controller - just hook direct - they put out 12v and are made purpose built for this - they still carry them, friend bought two this year.

[lewster]

Originally Posted by Mike91208

This worked great for keeping the batteries topped off. (I've since sold it as I installed three solar panels on the roof.)
Amazon.com: BatteryMINDer Solar Charging System - 12 Volt, 15 Watt Panel, Model# SCC-015: Automotive

I have used the BatteryMinder systems for very small maintenance applications, and they have performed admirable…..even with a 15 watt panel. The strength is in the charge controller, which is a true 3-stage unit, is adjustable for battery type AND has temperature compensation.

While the 30 watt system from Amazon is higher power, the specifications of the controller are a total unknown, as no specifications are provided in the listing. I would go with the known quantity from BatteryMinder over the 'deal' every time.

[Kyle401]

For about the same price as the battery minder you could get a basic 100W kit. I would think that would be a better match power wise to your two batteries.

[drboyd]

[dznf0g]

I bought a 15 watt several years ago, but I didn't pay anything close to $160. I can't remember where I got it....I thought Northern Tool, but I don't see it on their website. I paid something like $70 on sale. 15 watts does work as a trickle charger for me. It puts out about 750 - 800mA in full sun and about 500mA in cloudy weather.

I always find my batts at 98 - 100% (per Trimetric monitor) when I go to pick up the AS. That's when I have stored it with the cutoff switch in the on position (draw = about 225mA).

Let me add: the 750 - 800mA is with the draw in place...so the panel is actually putting out over 700mA in clouds and around 1A in direct sun. The lower numbers should be used for overnight battery recovery figures.

[almcate]

For about the same price as the battery minder you could get a basic 100W kit. I would think that would be a better match power wise to your two batteries.

The Renology Kit that Kyle mentions sounds very attractive and I'm wondering how difficult it might be to use as a stand-alone portable rather than a roof mount. Living (and moving) full-time in our 27FB does limit my access to tools, ability to access roof, and my mechanical and electrical aptitudes are similarly challenged.
Looking at the wiring diagram from the Amazon link, appears the panel would directly connect to the batteries with controller mounted inside the battery box or attached to the panel. Does anybody make a case/frame for angled position to use/transport the panel...assume damage could be an issue if bounced around.
I think I read someplace that the 2010 Internationals are prewired for solar, so for a wiring weenie maybe an installed roof mount wouldn't be that much more expensive?

Thanks, Al

[Kyle401]

Originally Posted by almcate

Does anybody make a case/frame for angled position to use/transport the panel...assume damage could be an issue if bounced around.

There are several 100W folding panels that come pre-wired with a controller. Renogy, Instapark, and Go-Power all offer portables in the 100W range. All these systems come with protection during transport and alligator clips to connect direct to your batteries.

[almcate]

Before I pull the trigger on a portable unit, it occurs to me that something that light would be VERY portable. Chaining to a tree probably isn't the answer...anybody have a straightforward trick to make them LESS portable?