Stray Voltage

Stray voltage banner showing cows in a farm field

If you own or operate a livestock operation, you should be aware of the potential impacts of Stray Voltage.

What is Stray Voltage?

Varying amounts of low-level voltage may exist between the earth and electrically-grounded farm equipment such as metal stabling, feeders, or milk pipelines. These voltages are known as "Animal Contact Voltage (ACV)", "Stray Voltage" or "Tingle Voltage." Usually these voltage levels present no harm. However, if an animal touches a grounded metal object where these low voltages are found, a small electric current may pass through the animal. These low voltages may impact livestock behaviour and health.

What are the causes of Stray Voltage?

Stray Voltage can be caused by a variety of sources including farm wiring and grounding issues, unbalanced farm load, equipment faults, or voltage from other sources such as telephone lines, gas lines and utility electrical distribution systems.

What are the effects of Stray Voltage?

Signs typically include cows being nervous at milking, cows refusing to enter the parlour and anxious to leave, nervous or aggressive behaviour, as well as the reluctance to consume feed or water. More information on Stray Voltage, click to view the Electrical Safety Authority - A Farmer's Guide to Basic Troubleshooting of On Farm Stray Voltage.

How to reduce the impact of Stray Voltage

If the source of Stray Voltage is on your farm, you can perform mitigation measures such as installing a neutral isolating device, adding electrical bonding between contact points, upgrading wiring, or replacing faulty equipment. This work should be performed by a qualified electrical contractor and must meet the requirements of the Electrical Safety Code. If Oakville Hydro’s distribution system is the source of the Stray Voltage, we will take the appropriate corrective actions.

Contact Us

If you believe that you have a problem with Stray Voltage, please complete the Farm Stray Voltage Customer Response Procedure and Investigation Form and send it to us by mail at:

Oakville Hydro

861 Redwood Square

Oakville, ON L6L 6R6

Attn: Farm Stray Voltage Inquiry c/o Engineering Department

Or by email to

Or by fax to 905-825-5830.

We will contact you within five (5) business days to confirm that we have received your request and to arrange the date of our first visit to your site.