Steven R. Melvin¹, Extension Educator

Derek M. Heeren², Associate Professor and Water for Food Global Institute Faculty Fellow

Troy Ingram³, Assistant Extension Educator

Aaron Nygren³, Associate Extension Educator

Derrel L. Martin², Professor and Extension Specialist

Mitiku Mamo³, Assistant Extension Educator

Eric Wilkening², Undergraduate Research Assistant

Santosh Pitla², Associate Professor 

¹Southeast District, Nebraska Extension, University of Nebraska-Lincoln

²Department of Biological Systems Engineering, University of Nebraska-Lincoln

³Northeast District, Nebraska Extension, University of Nebraska-Lincoln

Center pivot irrigation systems have several potential hazards, so personal safety is a priority. Hazards range from missing driveshaft covers to possible falls from ladders and towers. The primary safety concern is electrical safety, since many center pivot systems use a high voltage (480 volt) power supply to pump water and/or to run a number of electrical motors at the towers used to move the system. If not properly wired and grounded, the combination of metal structure and wet environment will increase the likelihood for electrocution.

The manufactures have done an excellent job of producing safe equipment, which are by in large installed by qualified dealers and electricians. However, the fact that 3-phase, 480 V power is being used, safety must always be a top priority because it can be fatal. The following is a partial list of some important safety and maintenance tips for center pivot irrigation systems: one him

Figure 1. Center pivots often use a 480-volt power supply. In order to minimize risk of accidents, it is important to ensure proper wiring at the center pivot, at the pump, and connections to the power supply.

• The most important rule of thumb is that all equipment will fail. Job one for the manufacturer, installer, operator, and maintenance personnel is to make sure when electrical devices fail, that it fails in a way that protects human and animal life..
• Always touch high voltage equipment first with the back of your hand because if it is hot and you grab it with your fingers, you may not be able to let go.
• If you suspect a problem with the equipment, fix it right away by calling your dealer if you are not qualified to do the work yourself. Slugged fuses will kill people. A slight electrical tingle today may indicate a problem that may be fatal under different conditions tomorrow.
• A person should always check wires with his meter before the electricity is turned off to make sure the meter is working, then turn the power off and recheck the wire to make sure the right switch is turned off.
• Pivots are long machines making it impossible to always see if someone is working on it. So always lock the disconnect in the OFF position when servicing the machine to prevent another person from turning it back ON and injuring or killing you.
• The main switch in the pivot panel does not turn off all of the power inside the panel. So if you need to work inside the panel to fix a problem or clean out a nest from a mouse that got in the panel through conduit that was not properly installed, make sure to turn the power off to the panel or call your dealer if you are unsure how to turn it off.
• Stay away from pivots if lightning is in the area because they are notorious for being struck.
• The biggest safety hazard is not having the 4th wire present or correctly connected all the way back to the power grid or generator. Having the grounding rod correctly installed and connected is important, but is not a foolproof personal safety device by itself. Grounding rods can be installed in situations where it is of little good because of soil type or after a lightning strike. Some dealers have meters to check the rod installation for its resistance level.

After electrical concerns, the second biggest safety hazard with pivots is missing driveshaft covers.

Additional Resources

To learn more about the topic of electrical safety for center pivots, see the following references:

-          Marek, T., and D. Porter. 2018. Think you understand center pivot safety and maintenance – really? Central Plains Irrigation Association (CPIA) Central Plains Irrigation Conference, Colby, Kans. 7 pages.

-          ANSI/ASAE S397.4 NOV2013 (R2018). Electrical Service and Equipment for Irrigation. American Society of Agricultural and Biological Engineers: St. Joseph, Mich.

-          ANSI/ASAE S362.2 JAN1983ED (R2014). Wiring and Equipment for Electrically Driven or Controlled Irrigation Machines. American Society of Agricultural and Biological Engineers: St. Joseph, Mich.