The submersible pump is an important equipment for pumping water in deep well. When used, the whole unit dives into the water to extract groundwater to the surface. Simple point said, is to a certain weight of groundwater from the location of the underground water is needed to boost to the ground, underground water volume per unit time ascending is known as flow, then ascended to the height of the ground is the head (it should be said that the main part of the head, should also include pipeline resistance and outlet pressure requirements, don't do a detailed discussion here)...     So is the elevation of the underground water pump installed or the water level of the well?   First, let's look at two nouns - static water level and moving water level:   The water level of a well is high. The water level has a static water level and a moving water level. The water surface elevation above the pumping water is called the static water level (i.e., in the figure above -ls). When the water is switched on, the water surface of the well will decrease with the pumping time, and the water level of this change is called the moving water level. When the water pump is relatively stable and the water level drops to a certain depth, the water level of the water level is stable. Generally speaking, the moving water level refers to the stable dynamic water level (i.e., the above - LD). The vertical height of the water level from the static water level to the moving water level is the depth of the water level falling in the process of pumping water or the depth of the pumping water (i.e., the -s in the figure above).     Then, according to the height difference between the water level and the water level of the water pump when the water pump is working, as the lifting height, it should be based on the dynamic water level (i.e., in the figure above -ld) as the head lift.     If the installation position of the pump is too large as the head of the pump, the cost of the equipment procurement will be wasted first: the electric pump should be large, the pipeline cable will be longer, and the operation will be charged. At the same time, it also causes heavy flow overload in the operation of the pump, which can easily cause the motor to burn down.     If the static water level is selected as the lift, it will cause the selection to be too low, and the running time will be insufficient or the water will not be drained at all...     Therefore, the high water level of the deep well pump is necessary to select the moving water level! Dynamic water level! Dynamic water level!     The important thing say 3 times, hope everybody can know, thank!