Solar panel wiring

[sogood]

I'm currently installing a solar panel on my boat, just to keep the main "starting" battery topped up, while the boat sits on its' mooring. But I'm considering incorporating the option to switch between the starting battery and the leisure battery. The solar panel has a regulator wired in, which shows, amongst other things, the state of the battery on charge. So, I was thinking of, rather than just wiring the panel to a single battery, to install a battery switch, as is used on any dual battery set up. This would allow me to switch between batteries, as required. The conventional battery switch set up, allows you to draw power FROM one or the other, or both batteries. I would just be reversing this, allowing power TO one or the other battery.

​Does anybody see anything I'm missing? Any thoughts appreciated.

 

[alldodge]

Don't see any issues with switch(s) to change which battery gets the solar power charger.

Only thing to keep in mind, is the solar battery chargers are almost a waste of time. They simply do not put out much power on a good day, and most days are not full sun

 

[Silvertip]

Solar panels are a target for thieves and unless you install one with sufficient output, it would be a waste. Whatever rating you intend to use, cut that rating in half because full sunlight is only available 50% of the time, and if you live in an area where weather is frequently cloudy and rainy, cut that capacity even more.

 

[KD4UPL]

Your switch idea will work just fine. But, I think a better solution would be to connect the batteries together with a voltage controlled relay (also known as an automatic charge relay). Blue Sea makes a nice one. This would allow both of your batteries to charge at the same time from your solar panel or from your engine when it's running.
If you are looking at one of the small little 15 watt or so panels advertised as battery chargers then I agree with the other two guys, it's probably pointless; they're too small. I would be looking for something like a 100 watt panel or larger. Remember, the larger the panel the less expensive it is on a watts per dollar basis. A 100 or 150 watt panel would go a long way toward keeping your batteries charged up.

 

[sogood]

Many thanks for the responses. As mentioned, size might be a consideration as the panel I'm using is only rated at 30 watts. It may need upgrading in the future! Theft is not a concern as such things go simply don't arise where I live and Moor. At least so far. Food for thought regarding the relay. The battery switch currently fitted allows for one or other or both batteries to be switched on at any time. Would this do the same job, given that the panel comes with its own charge regulator? Thanks again.

 

[alldodge]

The battery switch changes which battery is being charged by the alternator, don't use it to change which one is connected to the solar. Also don't leave the switch connected to both when using the solar. If one battery is weak or goes bad the solar will not be able to keep them both up, so the weak one will bring the other down

 

[sogood]

The battery switch changes which battery is being charged by the alternator, don't use it to change which one is connected to the solar. Also don't leave the switch connected to both when using the solar. If one battery is weak or goes bad the solar will not be able to keep them both up, so the weak one will bring the other down

I think we might have our wires crossed here.(no pun intended) I wouldn't be using the current battery selector/isolator switch with the solar panel, but fitting a similar switch on the solar panel circuit. The regulator on this circuit decides which battery needs the charge if both are connected at the same time. I would only tend to use the solar panel when the boat is at rest/ moored.
Thanks for the input.