Solar Sans Controller

[James P M]

I thought I once saw it somewhere here.... I've searched, but can't find the answer to this one:

While not connected to any other source, why not run the output of a small solar panel( 1 amp max, let's say) through the trailer's converter by way of the 7-pin charge line without bothering with a controller? Won't the converter-- to some extent-- "control" what's entering the battery? Does the converter care a whole lot what its 12 volt source actually is? Won't the converter just go ahead & charge?? Or are we talking damage/smoke/meltdown/China syndrome? If damaged by a smaller input-- What part of the controller would be damaged?

[Mike Taylor]

The converter in the trailer doesn't regulate the D.C. charge line coming in from the 7 pin connector. That regulation is done through your vehicles voltage regulator controlling the alternator. You will still need a small charge regulator for the panels if going through the 7 pin connector. The only charge regulation the converter does is when it is hooked up to A.C. power.

[Bud Kennedy]

If you have a large battery like a group 24 or so then you can safely connect a one amp solar panel directly to the battery without doing any harm. In fact the original controller in my U-haul was toast so I connected my 15 watt panel in directly. It has been that way since last winter and the battery sits happily being fully charged but not over charged.

However ---- be sure to install a blocking diode in the circuit lest the solar panel drain the battery over night.

[Gina D.]

your converter takes 120v AC and converts it to 12v DC. It would do absolutely nothing with a solar panel as the input. It also has nothing to do with your pigtail.

You can run a solar panel output through your pigtail. I did it with my Burro as a direct source to the battery after my charge controller. Just make the pictail end of your solar panel with a 7 pin socket, only using the ground and charge pins, of course.

You can go up to 15 watts without a controller and not worry about boiling the battery.

[James P M]

Many thanks to all for all the fast info. I guess I'll go ahead & try a 15 watt panel on the charge line.... until I can get into something somewhat larger.