Why is it critical to monitor the speed of a variable-speed pump?

Monitoring the speed of a variable-speed pump is crucial primarily to prevent cavitation from occurring. Cavitation happens when the pressure in the pump drops below the vapor pressure of the liquid, leading to the formation of vapor bubbles. When these bubbles collapse, they can cause significant damage to the pump components, including erosion and pitting of the impeller and casing. By carefully controlling the pump's speed, operators can maintain the appropriate pressure levels within the system, thus reducing the risk of cavitation and ensuring optimal performance and longevity of the pump.

While maintaining fluid temperature, reducing power consumption, and increasing flow rate are also important considerations in pump operation, the specific focus on speed monitoring is most directly linked to the prevention of cavitation, which can have immediate and detrimental effects on the pump's efficiency and durability.