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ChopperBill
02-14-2008, 01:30 PM
have my 110w panel and controller all set up so it is portable. Think I want to put a small one permanent on the roof just to maintain the batteries. What is the smallest panel that will do that for two 6v batteries? And do I have to add another controller to for it? Thought maybe something around 20w just wired directly to the batteries.

jpmorgan37
02-14-2008, 02:04 PM
Bill;
I had a 5 watt on my Sea Breeze and it kept two T-105 up when it was stored. I have one on my GC but it's never stored now. I have two 12 volts and if I figured correctly, it would keep them up too.

ChopperBill
02-14-2008, 02:27 PM
Dont need a controller with those small panels?

jpmorgan37
02-14-2008, 04:12 PM
Bill;

If it has one, I've never found it. The charge rate is so small that I don't think that it is necessary. If your total battery voltage is down to 10 volts, the most that mine would put out would be 500 mA. As the battery charged up, it would drop down to under 300 mA. About the only thing that I did was check the water level periodically. I will try to find out for sure and let you know.

John

jpmorgan37
02-14-2008, 05:11 PM
Bill;

I received my answer from the factory. No controller is used or needed with the 5 watt solar panels. I would just keep a periodic check on the fluid level in the batteries. The T-105s have a fairly large reserve so I would say about once every 3 or 4 months should be sufficient.

John

ChopperBill
02-14-2008, 05:50 PM
Thanks John. I just did some reading up on them and a supplier I priced said no controller would be needed for a 5 watt panel. I cant see where the say that about anything larger so I guess about 5 watts is it.

1duffer101
02-16-2008, 12:54 AM
retired4fun

A 5 watt solar array is 34.99 at harborfreight.com. looks like it has a cable and clips

ChopperBill
02-16-2008, 04:15 AM
Thanks duffer! Thats about half price of the one I was looking at.

fishn2dmax
02-18-2008, 02:31 AM
If you don't use a controller, you will need to put a diode in series between the panel and the batteries. A basic 1 amp diode at radio shack should do the trick.

Place the diode on the + side of the panel. The diode will have a symbol " >| " indicating Anode and Cathode. Place the lead with the "|" side to the battery and the other to the panel.


The diode will allow current to flow from the panel to the battery, but not from the battery to the panel when there is no sunlight. If you don't place a diode in series, the panel could will draw from the battery at night, so the net effect of the panel in reduced.

If you live in an area that has limited sunshine ( or snow)during the winter months, a 15 watt panel minimum will be needed to maintain two batteries. :)

ChopperBill
02-18-2008, 04:49 AM
15 watts will probably kill the deal for me. I was just looking for something relatively inexpensive to keep the batteries up in storage. I have a truck camper and the Bighorn both with 6v batteries. I generally take my Honda 2000 to the storage lot (less than 5 minutes away) and run it for a couple of hours on each.

jpmorgan37
02-18-2008, 09:18 AM
Bill;

When we lived in Minnesota, the 5 watt panel did the job just fine.

John

ChopperBill
02-18-2008, 11:02 AM
For forty bucks I just might give the Harbor Freight one a try. Thanks Gang!