sliperoren3

hello! i will do automatic switch for renewable energy application at home. the power source come from main sources and solar panel. so, automatic switch can switching either solar or main power supply without human selected. from the control pic circuit, did i should add some external circuit such as of optocoupler?because output of my project is 240V/50Hz. i have used the relay as mechanism part of hardware to swithing. how shold i maintain the frequency of power supply? ??? Thank you.