| 摘要 |
PROBLEM TO BE SOLVED: To provide a variable speed water supply device having a plurality of motor pumps driven at a variable speed, and performing stable additional operation with reduced pressure fluctuation. SOLUTION: The variable speed water supply device comprises: a plurality of pumps 1; a plurality of frequency converters 2 each having current limiting function for variable speed operation of each pump 1; a discharge side pressure sensor 4; and a control device 15 controlling these devices, and performs parallel running of the plurality of pumps 1. The control device 15 performs variable speed operation of a variable speed pump to match detection pressure of the discharge side pressure sensor 4 with target pressure, and starts an additional pump when the electric current limiting function can work in the frequency converter 2 driving the variable speed pump and the detection pressure of the discharge side pressure sensor 4 is target pressure or lower. COPYRIGHT: (C)2009,JPO&INPIT |
