The circuit is intended to control the charging of a 12v 7ah battery by a 10w, 24v volt solar panel.
Could you explain in more detail how this circuit is supposed to work? Where did you get it?
And how are you down-converting the 24V power source to charge the 12V battery? What kind of 12V battery is it (lead-acid, etc.)?
How are you ensuring that you are drawing power from the Solar Panel or Windmill at its Maximum Power Point? I don't see any MPP management circuitry or voltage conversion circuitry in this schematic....
I guess the way I see it is a voltage sensing circuit with some adjustable hysteresis that switches the battery in and out of the charging circuit. That part should work but there is nothing that steps down voltage or limits current. A good start but not complete.
I guess you are referring this site - http://www.mdpub.com/555Controller/. The site provides a good looking schematic and comparison but unsatisfactory explanation on how it works and why you should be doing few things like they've been told to.
The 555 can do more than what it does in that circuit (search more about this). And I don't think that is a charge 'controller', probably just some hysteresis implementation with facility to switch between dump/charge mode, as Averagesupernova pointed out.
Lastly, (connecting your other thread on wind turbines) I don't think this circuit will charge your battery from a wind turbine, which might be a an alternator if you're thinking about. Solar just might get away with it.
I suggest you to do some self study on 555's, charging process of a battery (or batteries) and Power & V-I characteristics of solar panels. Blindly following an electrical DIY is not recommended.
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