Why must you use variable speed drive in pumping applications?

Variable speed drive in pumping controls motor input voltage and frequency thereby controlling the pump.

Variable frequency control consist of primary circuit converting alternating current (AC) to direct current (DC) then converting it back to AC with regulated frequency

Benefits of variable speed drive;

1. Reduce cost and save energy. Controlling pump speed to match system requirement helps avoid energy wastage and reduce operation cost. It is majorly useful in application where demand for water varies within the day or season, they include industrial and irrigation systems
2. Variable speed drive provides control and reliability for motors / pumps. Variable speed drive adjust to changes on demand preventing mechanical stress on the pipeline thereby reducing risks of system failures and costly maintenance costs
3. Use special motor at high speed. It is possible to configure drive to run pump upto 500hz
4. Easy start-up commissioning, configuration and maintenance through softwares

Properties of variable speed drive

1. Stopping pump at zero demand
2. Stopping pump incase of water failure
3. Motor thermal protection
4. Low flow or low flow protection
5. Dry run protection
6. Cavitation pump protection
7. High flow protection
8. Outlet pressure protection
9. Low pressure protection