Bought some solar panels

[Airspeed]

I bought my wife a flip down LCD/DVD player for our tear so I bought four 12 volt 5 watt VW solar panels to help offset the power she will use to watch it and each comes with a some type of controller attached to the wire, I'm not sure if it is just a diode or an actual controller as I havent received the panels yet, anyway, do I need to run each panel through their own diode or can I wire them all together and run all four through one?
I think I got a good deal on these,They are brand new and I only paid $60 for all four of them, hopefully I will get close to 20 watts out of them.
Does anyone have any experience with this type of solar panels?
Any info would be greatly appreciated! Thanks!!! Aaron

[billnut]

It's most likely a diode to keep the bat. from feeding back into the solar and yes you got them at a great price. I power every thing in my hobby room with solar and a good controller for my setup was $$$
BILL

[bdosborn]

Aaron,
I bought one from eBay as well to play with. There's already a blocking diode in the charge line for the panel so you don't need to add one. Just don't cut the little grey box off where it lives or the panel will run the battery dead at night. You probably got the new style panel with the OBDII connector. Just cut that off if you want to hardwire the panels to your fuse box or if you want to add a cigarette lighter plug to it. There are two wires in the charge wire, a red one and a black one. Red goes to positive and black goes to negative. Wire the four panels in parallel, or connect all the red wires together and then wire them into your fuse block.

You probably won't need a charge controller for 20 watts but you're right on the edge of needing one. I would get a one if you plan to use the panels to maintain your battery over time. I've got a Sunsaver charge controller for my panel and it seems to work pretty good. While its not as efficient as some of the new MPPT controllers, its fine for this application and cheap. I'd go with a Sunguard controller, which is the smallest Sunsaver controller in a potted package (ie the cheapest version in the Sunsaver line).

Bruce
P.S. The VW solar panel isn't waterproof so you'll want to keep them out of the rain.

[Airspeed]

Thanks! I went ahead and bought a charge controller,hopefully I got the right one? It only cost me $30 on EBAY. It says it has a built in diode and a bunch of other stuff. I may buy a few more of the vw panels if these work out well. Thanks! Aaron

[bdosborn]

It looks like that controller has an automatic load disconnect if the battery voltage gets too low. Nice find.
Bruce

[Airspeed]

The guy on ebay has more if anyone needs one,
http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... B:EF:US:11
Aaron

[sledge]

I bought one out of a brand new VW Beetle , and use it on a GS750 Suzuki that has a bad stator in it........ as long as I don't run the Headlight , it will keep a Motor Cycle battery hot enough to use the electric starter and ride the bike all day.......... I have put about 200 miles a day on it using the VW panel ..... and when I got home the battery was showing over 12 volts.... they work good.