The Logic SP-STP-TP series is a pump management range that controls and protects surface pumps and submersible pumps. These VFD - variable frequency drive controllers integrate the energy improvement efficiencies of variable frequency drive technology within a simple to use, plug and play, module while maintaining pressure and flow in a system. In addition to the day to day savings of reduced energy consumption, further economies are made during install as pressure sets fitted with a Logic controller do not require expansion tanks, check valves, pressure gauges or expensive control panels. For multi-pump booster sets applications, the Logic SP-STP-TP-COM versions will provide integral and automatic pump changeover to guarantee even wear of the pumps, reducing the risk of pump failure and costly downtime. Both versions enable pumps to operate at a variable speed to ensure the correct flow of water at the set pressure.