3%～5%。 The pump was designed with a solar energy intelligent control system and the running process has been controlled by a PLC program. While the pump ran at off-design conditions, the intelligent control device could automatically adjust pump speed to prove working stability at the given conditions. Intelligent alarm control device was also used and the alarm would immediately in operation to stop the pump under the failing conditions, such as higher temperature, lower oil pressure, lower oil level, bearing wearing, and mechanical seal damage. The control system could also be used for remote operation. The self-priming pump was designed with a jet structure. When the self-priming process is completed, the valve on jet can be closed automatically, from which the efficiency of the pump can be increased by 3%～5%.