Some centrifugal pump users mistakenly believe that the lower the water lift, the smaller the motor load. Under this misapprehension, when selecting a pump, they often choose one with a high water lift. In fact, for centrifugal pumps, once the pump model is determined, the power consumption is directly proportional to the actual flow rate of the pump. The flow rate of the pump decreases with the increase in water lift, so a higher water lift results in a smaller flow rate and lower power consumption. Conversely, a lower water lift leads to a larger flow rate and higher power consumption. Therefore, to prevent motor overload, it is generally required that the actual water lift for pumping not be lower than 60% of the rated water lift. Hence, when using a high water lift for low water lift pumping, the motor is prone to overload and overheating, which can even lead to motor burnout. In case of emergency use, a regulating gate valve on the discharge pipe (or using wood or other materials to block the small discharge opening) must be installed to reduce the flow rate (WeChat: Pump Master), preventing motor overload. Pay attention to the motor temperature rise, and if the motor overheats, the flow rate at the discharge opening should be reduced or the motor should be turned off. This is also a common misconception; some operators believe that blocking the discharge opening to forcibly reduce the flow rate will increase the motor load. In reality, the opposite is true. On the discharge pipes of regular high-power centrifugal pump irrigation units, a gate valve is usually installed. The reason for closing the gate valve first before starting the motor and then gradually opening it is to reduce the motor load during startup.