You can use this to control a solar array or wind generator.
The voltage source on the left is a reference voltage, I would use an lm 7805 for this, the voltage source on the right is from the battery, the voltage source at the top is the solar array, pot at the bottom controls the cut out voltage.
As it is set now the relay dumps the solar to a dummy load at 14.2 volts.
You must use a relay rated for the wattage of you solar output!!!!!!!
With this you can use the dumped power for another load after the batteries are charged
