I live in Kolkata. We have a underground water storage tank with 4000 ltrs. capacity & also a rooftop storage tank . Basically i want to know how can start the water pump automatically when rooftop tank becomes empty. I also want to know if it is possible to ensure that if the underground tank is empty the pump will not start? Can i make this arrangement in this case?


 Subrata Panja
 subratapanja_123@yahoo.co.in