
Stray Voltage – What Is It and Why Don’t Cows Like It?
Today, dairy farms and agriculture in general are using variable frequency drives (VFD’s) to automate processes, increase productivity, reduce operating expenses, and ultimately increase profits.
VFD’s are integrated all over farms – well pumps, vacuum pumps, fans, irrigation pumps, and manure scraper systems, to name a few. While they provide significant energy savings, VFDs create problems with power quality that affects cables, motors, programmable logic controllers (PLCs), electronic equipment, utility compliance, and especially cows.
A significant issue that VFDs create is stray voltage. Stray voltage can affect many areas of your farm including the well-being of cows. It can even lead to reduced milk production and ultimately lost revenue.
MTE has over 40 years of experience diagnosing and providing power quality solutions to issues generated by VFDs. We can help provide a solution that will make both you and your cows very happy. Read below to learn how stray voltage can negatively impact a cow’s health and production, and how MTE can help.
And remember, happy cows produce more milk!

Stray Voltage in Water
A VFD that’s connected to a well pump can transmit stray voltage to cows through the water they drink in watering tanks. Cows have a super sensitive nervous system, so even if they detect minor electrical sensations from stray voltage, they won’t drink enough water and will therefore produce less milk.

Stray Voltage through Milking Machines
Stray voltage from VFDs that drive vacuum pumps can travel through metal pump lines and transmit to cows through milking machines and stanchions. Because cows have a sensitive sense of touch, uncomfortable stray voltage may prevent them from releasing their milk, thus reducing production. It can also deter them from eating which also hurts their health and production.

Stray Voltage Interferes with RFID Readers
VFDs anywhere on farms can cause another problem that impacts farmers more than cows. Stray voltage interferes with RFID readers so that they can’t read signals from RFID tags and collars. Without capturing critical info on cows, production history and biodata is lost.

MTE’s Nexus Filters will Make Your Cows (and You) Happy!
MTE manufactures special devices called electrical filters that counter and remove stray voltage produced by VFDs. Cows are able to drink, eat and be milked without experiencing stray voltage. Hands (and hooves) down, our SineWave Nexus® filters are a cow’s best friend! They’ll be “udderly” thankful that you installed these filters!