VSDs as electrical savings devices on centrifugal irrigation pumps

By J Starke and A Chalmers, Irri-Gator Products


Published in:

Electricity+Control, September 2013 (pages 48 - 50)

Enquiries: Tel. 083 231 5877 or email johns@irrigator.co.za

Tel. 082 490 5922 or email alisterc@irrigator.co.za


The full article on VSDs as electrical savings devices on centrifugal irrigation pumps can be downloaded in PDF format.


The most commonly used irrigation pump on farms is an end suction centrifugal unit driven by an electric motor. These are generally fitted to a common base plate and close-coupled by means of a flexible tyre coupling. There are an increasing number of variations of centrifugal pumps being used such as the vertical multistage; submersible multistage pumps; however most times the same principles will apply to these.

When investigating the possible unlocking of energy savings on irrigation pumps it is imperative that the hydraulic design of both the pump and the whole irrigation system is analysed. This requires the expertise of an irrigation designer who is knowledgeable in the practical application of the variable speed drive (VSD), has an understanding of the Laws of Affinity and general irrigation design practices. The management style of the farming operation, including the power supply tariff structure which is applicable to the farm, also plays an important role.


Take note

  • VSDs can play a role in improved energy efficiency – but the application must be fully understood.
  • Operators of various types of equipment must be well versed in the use of the equipment.
  • A VSD can play an important role in energy saving if it is used and managed appropriately.