Industry Spotlight: Using VFDs for Irrigation and Farming

By Yin on 16th Feb 2015

Spotlight on Industry: Using VFDs for Irrigation and Farming

Irrigation and farming systems are constantly changing as new technologies and improvements are introduced. The introduction of the Variable Frequency Drive (VFD) for irrigation and farming applications is no exception. Read below to learn more about the effect VFDs have had on the way many irrigation systems used in the farming industry are designed and used today. 

Without a VFD:

Traditionally, many of the pumping systems used to irrigate farms are oversized and over-designed in order to account for any extreme conditions or uncertainties. Since these systems are oversized, the pumps are not optimized to run at maximum efficiency. This has been a major concern in the irrigation and farming industry—namely because it means less profitability for farms and farmers because of the high cost to pump water, a result of inefficient systems.

With a VFD:

While pumps are oversized for several reasons, inefficiency with an oversized pumping system is not an issue when the pump is operated with a VFD. This is because the VFD is able to control the flow and pressure of the pump making the overall size of the pumping system no longer a concern. Being able to control the pressure and flow of the pump during operation gives the ability to run the pump at maximum efficiency levels for increased energy savings. Using a VFD also eliminated the need for other often less effective means of controlling the pump speed such as control or throttling valves, bypass lines, or even multiple pumps.

There are several benefits to gain from using a VFD on irrigation systems aside from the energy savings, another of which is reducing water hammer. Water hammer can be a serious problem in irrigation systems and can be severe enough to burst lines in some situations. A VFD can help eliminate this problem by softly starting and stopping the pump so that the quick energy change that is usually developed within the system when the pump is suddenly turned on or off does not develop, effectively eliminating water hammer.

Additional VFD Benefits Include:

  • Reduced wear on pumps and motors
  • Replaces need for pump control valves
  • Advanced control with use of transducer
  • Remote start abilities and more

Recommended equipment:

Irrigation systems are often located outside so that they are close to the water pumps, and wells that they receive their water supply from. For outdoor applications like that, it is important that the VFD system is protected from exposure to weather, dust, heat, or other environmental factors. Let’s take a look below at a type of VFD system that would work well for many outdoor applications seen in irrigation and farming systems.

Enclosure:

The Motor Drives International (MDI) F3R is a VFD control panel specifically built for the outdoors. Below you can learn why:

  • The 3R in F3R stands for NEMA 3R, an enclosure designation indicating that it is specifically for outdoor use.
  • Distinctive white enclosure designed to dissipate heat by as much as 20%.
  • Rain hoods with washable poly filters underneath to protect against moisture and dust (a concern for dusty farming areas).
  • Special outdoor cover used to protect the controls mounted on the outside of the panel so that the system can be operated without having to open the panel.
  • Pad-lockable door handle for safety and security (an important consideration if the panel is in a rural area without regular attention).

Inside the Enclosure:

  • The VFD inside the F3R is a Mitsubishi F800, a drive specifically designed for use with pumps and capable of several advanced abilities for pumping applications.
  •  Redundant fans to ensure that the equipment is kept cool even one of the fan fails (a useful feature if the panel will not be under regular maintenance).

To learn more about the F3R, take a look at our in- depth F3R article currently featured on our blog. If you think the F3R would be a good fit for your application, pre-built and in stock options are available for purchase today.