... -clog, auto-coupling, hi-reliability and auto-control Pump adopts cooling jacket for power bigger than 18.5kW ... , keep the pump operating safely under the lowest water level QW ... engineering, industry, hospital, hotel for pumping sludge, sewage and city life sewage Rated voltage: 380V (660V) Frequency: 50Hz, ... to keep the optimum operation conditions submersible sewage pump