For high rise with multiple break tanks and roof tanks, is VFD pump the best choice for transferring water from the suction tank ? For my understanding, VFD pump is best suit to the system with high friction rather than high static head. Please advise me the best pumping system. Thank you.
VFD can be applied to positive displacement pumps if necessary for providing sufficient pressure. You should discuss your application with the appropriate pump suppliers to see if VFD will be beneficial for your particular operating conditions.