Suction lift refers to the negative pressure on which side of a pump?

Suction lift specifically relates to the pressure conditions in the suction side of a pump. When we discuss a "suction lift," we are referring to the scenario where the atmospheric pressure is used to push the fluid into the pump from a lower elevation. In such cases, the atmospheric pressure on the fluid enhances the flow into the pump as the pump forces the fluid to move towards the discharge side.

Since pumps are designed to create a differential pressure that allows fluid to be drawn in, any negative pressure or vacuum occurring on the suction side means that the pump must be able to overcome this negative pressure to lift the fluid effectively. Thus, a suction lift is measured as the vertical distance water must be raised, influenced by the negative pressure generated on the suction side, allowing the pump to operate efficiently.