Stray voltage is a low-level voltage (less than 10 volts) present on metal equipment that has been either grounded to the electrical system or connected to the grounded neutral conductor. Although stray voltage is present on all active distribution systems, humans usually do not notice it. Some types of livestock, especially diary cows, are particularly sensitive to it.
What should I do if I suspect stray voltage on my farm?
Start the problem-solving process by taking all of the following actions:
- Contact Agralite and explain your concerns. Agralite offers stray voltage investigation at no charge.
- Have a licensed electrician inspect the wiring on your farm. Make all necessary wiring connections.
- Remember that the safety concerns related to some wiring problems are more important than the stray voltage problem. By correcting safety hazards, you may solve a large part, if not all, of your stray voltage problems.
- Have your milk equipment dealer check out your milking system.
- Contact your veterinarian to help you address any herd health concerns that may or may not be related to stray voltage.
What are the symptoms?
A dairy cow affected by stray voltage may show symptoms such as:
- nervousness during milking
- reluctance to use metal waterers or feeders
- unexplained drops in milk production
- incomplete milk letdown
- increased mastitis
- elevated somatic cell count
However, diary producers should remember that these behavior changes also can occur due to problems with milking equipment, changes in milking routine, spoilage of feed or pollution of drinking water. Therefore, all potential sources for behavioral changes should be investigated.
What causes stray voltage?
Causes can vary. Some common sources are found both on and off the farm.
- improper wiring
- poor grounding
- unbalanced 120 volt loads
- faulty equipment
- poor or corroded connections
Because of high electric use, high humidity and corrosive silage acids, urine and manure, a dairy farm is not the ideal environment for electrical wiring and equipment.