Stray voltage

What is stray voltage?

Stray voltage is the general term used to describe low-level voltages that may be found between surfaces that animals contact. On a farm, these surfaces may include stanchion pipes, water cups and feeders.

Generally, sources of stray voltage exist on all operating electrical systems. Although stray voltage can’t be totally eliminated, it can be minimized.

Causes of stray voltage

Many things can contribute to stray voltage. Some sources include:

Inadequate connections on the neutral or ground wire system.
Poor grounding conditions.
Undersized neutral conductors.
Dirty, dusty, corroded or damaged electrical boxes and devices.
Unbalanced 120-volt loads.
Defective electrical equipment.

Acceptable stray voltage levels

Studies by the U.S. Department of Agriculture and several universities have show that individual cows react differently to various levels of stray voltage. This research supports prior research that says that stray voltage of 2.0 volt AC or less should not cause health or production concerns for livestock.

Symptoms reportedly associated with stray voltage

Nervousness during milking.
Reluctance to enter barns, stanchions or milking parlor.
Uneven milk out.
Reduced water or feed intake.
Low milk production.

These same symptoms have also been known to be caused by non-electrical farm issues like improper vacuum or milking equipment, inadequate ration balancing or illness.

Free inspection

If you have questions about stray voltage, please contact us. We have field representatives in your area that can work with you and answer your questions. We will conduct a cost-free investigation on your farm and schedule a follow-up visit to provide investigation results and recommendations.

If you decide to make changes on your farm, your local field representative will assist you with paperwork needed to take advantage of our re-wiring program. By participating in a re-wiring program, you can make your farm a safer place to work.

Stray voltage online resources