Selector switch

[Dark-hobo]

so I have a project in a class. And I need a selector switch for it. I need it to choose between a solar panel and a generator. I want it to switch to the generator when the solar panel begins to produce less electricity. Also Is there a site were there is just a database of schematics for stuff like this? Because I think I also need a switch for rerouting from one battery to another when the first battery is full or when the first battery is not even connected. Any details you need to help me I can give. sorry fro burdening you guys like this

[DaveW]

There isn't any chance you have access to a PIC board is there...

...sorry, i just think you can do everything with PIC's :D

Are you wanting to switch automatically between the generator and the solar panel, or manually? and also with the batteries? If it's manual, it's easy enough to do this, just some 3 way switches or something like that. If it's automatic, then it's a bit harder...so when power from the solar panel drops, you put the generator on...that could pottentially be tricky. I'll be honest i have no idea. I've studied logic gates, not electronics, so there's not much help i can give. If you find such a website, let me know.

-Dave

[snickells]

Hmm.... im thinking that maby you should go and talk to people who go fourwheel driving. The circut you want sounds very much like an dual battery set up in a long range vehicle. Or perhaps you should be talking to people who sell home solar power setups, they use banks of car bateries for storage and gennies for back up power. Either way, its not going to be cheap. But good luck! Post some piks if you do get this off the ground. ^_^

Steve

[Dark-hobo]

no i don't have a PIC board but I can get one. And yes I need it to be automatic.

[DangerRanger]

hey have you ever seen the emergency lights that switch on when the power fails?I believe they use an isolator similiar to what your talking about.If there is a certain voltage drop or increase it switches automatically.I dont know for sure how it works just popped up in my head that it switches power automatically.Maybe you could fins a schematic for em with the manuf.Google away.

[Dark-hobo]

I have a bit more detailed info now. It looks like the solar panels we will be using are going to be 1500-2000W total. Our power output is going to be 20A at 120V. We are going to have a set of batteries to charge. That will store a charge to in turn charge another set of batteries (electric car batteries). So I need the diesal generator to switch on only when the batteries get below a certain charge, say... 50-60%. I hope we don't do it grid tied though because it seems like it will get way more complicated if we do that. Because then I will need a second isolator/relay circuit to divert power when the batteries are full.

[opengswede]

Not sure if you need this anymore, but I ran into a link for an emergency light setup. It charges a battery if the power source is available and the battery needs charging. It also switches to the battery if the 230V power source is unavailable (basically a standard emergency light setup).

anyway, here is the link:
http://www.electronic-circuits-diagrams.com/lightsimages/lightsckt3.shtml
hope it helps.
-.e