Electrified Cows

Maybe an electric field meter?

http://www.lessemf.com/electric.html

If it doesn't help the cows you can also use it to play Ghost Hunters.

What indicators lead you suspect stray voltage is the problem?

Thanks for your response. You have given us a lot of fodder for experimentation.

We aren't certain exactly where the problem is. He is asking how to trace these types of voltages, and I'm not certain where to start. We are just assuming it's a small voltage as that is typically all it takes to affect a cow.

...and, if it's indeed stray voltage problem, check all the electric installation and check if he doesnt have a ground loop somewhere. This is usually the most common cause of the problem. Neutral from power supply MUST be grounded only in the power supply inlet. All other grounds, equipment housings, and anything that could be considered a source of grounding must be isolated from the neutral. May even be connected to the same ground as the neutral is, but do it only in that same point.

Thanks for all the good information.

He has separate panels in the house and in the milking parlor that are on the same service. It is typical to separately ground each service but I know he drilled a forty foot well and used it as his main ground. He has also bonded the services and a trenched in perimeter ground wire to this main ground.

From your comment it appears that both panels are bonded. Here is a reference drawing. Get him to check and make sure his panels are setup like this.

I must disagree with the drawing above.The NEC stipulates that a sub-fed panel shall not have the neutral (grounded) conductor bonded to the grounding (green) conductor at the subfed panel.This can create ground loops.It shall be bonded only at the main panel.Reference NEC article 547.9.

Also, a separate grounding conductor shall be run with the current carrying conductors.The grounding conductor must be of equal current carrying capacity as the largest current carrying conductor.The grounded(neutral)shall not be connected to the ground rod or panel at the sub panel.

The drawing above is not very clear, but I do not see a grounding(green) wire from main to sub fed panel.---------SSB---------------

As I am not an expert on the NEC, I will not argue with your statements other then to say...

I agree with you that a sub panel should be fed in the way you mention, if it is in the same building as the service feeding it.

The diagram I presented is expressly for a feed to an out building from a main building and is based on the Canadian code and is the suggested way of feeding an outbuilding when the outbuilding is to house livestock.

As to the missing bond wire you mention, when you ground the neutral at the second building, the bonding conductor is not required in the feed as you recreate the start of the bonding system at the neutral/ground interface at the second panel.

Here is the other way to do this, again based on the Canadian code and not for use in a building that houses live stock. This might look more like what you expected.

Exactly, you can also reference NEC article 250.24 (A)(5) which states "A grounded conductor shall not be connected to normally non-current carrying metal parts of equipment, to equipment grounding conductor(s), or be reconnected to ground on the load side of the service disconnecting means except as otherwise permitted in this article." What this is saying is the neutral must be "floated" (not grounded), at all points except at the service panel. This is typical farmer action, hook up whatever you want, however you want, then blame someone else. especially the utility. If you are doing a real investigation, and I am not sure that you are, I would suggest compliance with NFPA 70 should be your first priority. If you do not understand NFPA 70, as is apparent in the posts you have made, perhaps you should turn the task over to someone who does.

Isn't it amazing just how many do it yourselfers look into the service panel and see the neutral buss anchored to the panel and also see the ground buss anchored to the panel and believe that these are treated the same through out the wiring system and are therefore inter mixable. I can't imagine how often we see the bare or green ground connected to the neutral buss. It can work but how often do the installers get confused and mix them up. Maybe this farmer should consider installing GFI"s through his entire system. We know for certain that dairy barn floors are almost always wet either from scours,urine or just hoseing down for cleanliness.

TMF

very nice answer you get my GA on that one.

Converting everything to 220 would be a step in the right direction as it reduces current returned to the source via the neutral and reduces the voltage gradient between the "ground" and the neutral/bond system.

My comments about the utility "Y primary and Y secondary" talk to your next question. Yes.. if the impedance back to the source is less at your friends place then the impedance of the system at his neighbour (unlikely but very possible - I have seen it before) his system will return current for his neighbour back to is source, even if it is on a different distribution transformer, if the utility has a common neutral.

Since this is in the Midwest check the water tank heaters. I was sent on a call in Iowa many years ago anf found a pig farmre had wired tank heaters in without a ground and killed all of his pigs.

This is a problem in Wisconsin as well. http://www.wisconsinpublicservice.com/farm/stray.aspx This is a pretty fair primer on stray voltage.

I don't know what state you're in, but most should have a board to deal with stray voltage issues. Perhaps the state university or local electrical trades would be a contact point.

As for training cows to like shocks, I haven't heard of to many masochistic cows. Do any of the neighboring farms have problems, and what have they found out? Is there a co-op in the area, they would likely have more specific information for your area.

A very good contact is:

Stetzer Electric, 520 W Broadway St, Blair, WI 54616 Tel: 608-989-2571 Fax: 608-989-2570

They have successfully troubleshot the cow problems related to electricity.

Hi Age>IQ,

"I understand the stray voltage does not actually hurt the cow but sets up psychological avoidance behaviors which affects its health and makes them fearful and nervous which affects milk production."

I would start by herding the cows around the farm to find out what they are afraid of. Whatever they are afraid of is the place to look. Otherwise you can waste a lot of time going nowhere. It could be an induced voltage from the overhead lines.

Maybe having an electric containing fence is not the best idea. My dad used one when he wanted the cows to clean out the irrigation ditch, and to keep them away from the alfalfa. He had an old cow (about 12 years old) that would wait for one of the young heifers to get broadside to the electric fence then charge her to knock down the fence without getting shocked herself. Once the fence was down, there was nothing to stop her from eating the alfalfa.

S

Yes, it would be better to have just 220V system only, as two systems can react because of potential difference.

But real question is: How does Mr. Joe know it is >>stray voltage<< that is bothering his cows? From where was this conclusion drawn?

Dry grass can generate static electricity, and so can carpets or other floor covering...

I dont believe in story of electricity traveling back to electric central, as where would electric charge from thunderbolt that strike mountain or a tree and went to ground go?

Is it really true that there is 400 KV DIRECT CURRENT line still in use, when this is very ineficcient pover transmision system that was replaced by AC just because of great loss of power in such lines?

Anyhow, wet wall and wire nibbled by mouse can be source of electricity leak, so each circuit should have its own fuse, then one can test them one by one to see if meter is turning even when nothing is switched on. If it is line activated only when light is turned on, then each place should be tested on drop in voltage on light bulb wire.

Badly installed wires can drain electricity from one another if there is not enough insulation between them, but this need not leak otherwhere but is simply lost, at least that was story I heard from one old professionall electrician....

Last of all, I seems to remember that this same problem was discussed on some thread before, so better try to find it so we dont duplicate efforts.....

Thanks for your response.

Yes it is a 400KV DC line. That's why assume no induced voltage from a DC line.

When this DC line was proposed and installed back in the 1970's the farmers in this area opposed it passionately, claiming their would be stray voltage. They wouldn't listen to the fact that you get no induced voltages from a DC line. They would stage protests and even pull down towers with their large tractors. The power line zig zags through this area as you can see the planners had to follow the farmers path of least resistance. I recently asked an old fellow, that was strongly and actively opposing it back then, what was really the main issue and he said they wouldn't pay the farmers enough for the tower sites.

Hi Henrik14

You said...

"I dont believe in story of electricity traveling back to electric central, as where would electric charge from thunderbolt that strike mountain or a tree and went to ground go?"

Well... It happens all the time. Current will return to its source via every path that exists.

Notice I said "source" not "central". It happens quite frequently where we loose a bunch of consumer neutrals due to weather events and return current (from the unbalanced current of a consumers draw) will be carried by a ground return to the nearest pole ground then back to the common utility neutral, which is common to both the primary and secondary sides of the distribution system.

We burn poles this way quite often in some of our communities, as mentioned by another poster.

As far as the energy from a lightening strike is concerned, the earth itself is the return point so there is no where else for the current to flow to.

There is a 700km long 400 kvDC transmission line into Winnipeg, Manitoba as a hub. From Winnipeg the line goes to Duluth, MN USA. Another leg from Winnipeg continues down into Iowa / Nebraska.

So there is a lot of farmland under the DC transmission line.

In Quebec Provine, Canada and in Ohio / West Virgina USA there are 735 / 750 KvAC transmission lines.

In Japan there is an 1100 kVAC transmission line, there is a line of this voltage or higher planned in China. The powerline in Japan has an elevator on the towers to get workers up to the top. The towers in Japan have shielding lines between the towers to reduce the electric field intensity at ground level. The shielding lines help to reduce the required height of the towers. Other voltages mentioned above typically do not have shielding wires below the lines.

Nearly all transmission voltages have shielding wires above the transmission lines to reduce lightening damage.

There is one section of 345 kV AC transmission line in central Wisconsin that on one phase for 5 towers in a line the center ceramic insulator in the string of maybe 30 insulators was damaged, only lightening could have done this. There is a splice connector with corona and arcing sometimes in that section of line. I have watched it for most of 8 years. The neighbors across the highway said the top of the tower had glowed one night. The towers are next to a wet, marshy area so very good grounding, about 1/2 mile from a minor substation.

Your statement that AC is used over DC for power transmission is true. The irony is that AC has more voltage drop. This is because AC causes eddy currents (Lenz's Law) which force the current flow to the outside of the conductor (skin effect). The reason we use AC is because we can use transformers to step-up the voltage (reducing current and thereby reducing voltage drop) and then step-down the voltage close to the load. Special modern transmission systems can create high voltage DC for transmission which is very efficient because there are no eddy currents and the entire conductor is used!

Hi ''hot cows''

I came across this problem some 40 years ago on a remote piece of territory on the west coast of Scotland. Again the cows were getting 'jumpy' in the vicinity of an overhead nine pole supporting a transformer supplying several houses and a small farm stead from a 3.3kV single phase supply. There was a history of 'peculiar' things happening on the local supply network and a variety of equally bizarre explanations prevailed. My father an experienced electrical engineer suggested that the cause was due to substantial current flows in the earth return in the area. The local electrical supply authority , South of Scotland Elcrtricity had a stock solution to overcomig hot spots by installing ELCBs on the main incomer to each property considered as contributing to the problem. The key issue was that the troubled bovines only experienced the problem near to the pole where the the transformer was fixed and the trouble got worse in wintertime when the ground was really wet. Clearly the conductivity path was an important factor. No one ever measured the potential between the front and rear ends of the coos but they are probably more sensitive than we think!

Clearly the is an issue with the local installation which would become aparent if an ELCB was fitted as it would trip before the earth current got to a level sufficient to manifest itself in the 'hot cow syndrome.

Therfore sart by doing an insulation test on all the connected wiring and things like motors which may well have developed a significant fault to earth.

I can point you to a couple of places to start your search. First contact you local cooperative extension service they will have some resources at your state agricultural engineer school which will give you some assistance in testing.

Here are some links to information about stray voltage in diary barns.

http://www.mwps.org/index.cfm?fuseaction=c_Products.viewProduct&catID=712&productID=6129&skunumber=NRAES-149&crow=1

http://edis.ifas.ufl.edu/AE019

http://www.egr.msu.edu/age/aenewsletter/1_jan_feb_03/tinsey_1_30.htm#2

Finding the source of stray voltage can be difficult and will take some effort to track down.

Best of Luck, Mike

Thanks for all the good tips. I will be certain to try some of these.

Check with your power company. Stray voltage has been a issue for some farmers in Wisconsin. There was a law suite against WPS many years ago by our neighbor. He received a large settlement and is still milking cows (4600 of them).

Google: Wisconsin public service stray voltage

Below is one of the many sites that came up.

http://www.wisconsinpublicservice.com/farm/stray_overview.aspx

Good Luck and don't take any BS from the Electric Company in your persuit of justice.

I really think that you have isolated the source of your problem in a single line in the thread posting.

"The local REA Claims No Responsibility, AND: offers No Help!"

This issue was reported many years ago in an article that I read about the stray voltage associated with transmission lines that was adversely impacting a dairy farm. As can always be anticipated the local Utility Monopoly, be it an REA, or A Co-OP, or any other Monopoly, their first line of defence is is denial. Their Legal Advisers will always advise them to "Make You PROVE that their equipment is RESPONSIBLE for your losses. This can sometimes be a lengthy and costly effort. You can bet that if they find that you are getting close to proving that their equipment is the problem, they will very quickly begin making corrections that will impede your ability to hold them financially responsible for the problems that they cause. It is all about the money.

One way to isolate the problem is to bring in a standby generator source for your electrical power and have the REA disconnect the wires at the pole by the public right of way.

Make absolutely sure that it is properly grounded. If the problem continues in the milking barn, "and there only", you may find that the problem is the concrete floor not being sufficiently grounded.

These floors will have steel rebar throughout below the surface, but these surfaces will have microscopic cracks that will allow moisture to penetrate and said moisture will conduct current to the rebar and on to ground via the least restrictive route, through the wet cow and the wet equipment. Every milking barn I have been in has the cow restrained in the milking stall by some sort of metal bars, with the cow munching on wet silage, standing on a wet concrete floor, and connected to a metal "conductive" electric milking machine. When one considers the many avenues for positive current to flow to ground in this environment, isolating one from the other can be a time consuming problem.

In the end it was found that stray voltage from the utility was the problem! The Dairy Farmer prevailed in court, but to do so he had to prove that there was absolutely no other source electricity getting to the cows causing the problem!

Good Luck!

TooMuchFun

Age > IQ:

Public Service providers such as WPS (Wisconsin Public Service) is spending millions for this,

The cause is varied, some farmers took the provider to courts and actually won if you want to call it that, Attorneys are the only winner, while the farmer watches his herd get devastated.

As far as stray voltage, on an existing facility (barn) is difficult. Newer buildings they try to ground everything, Stanchions, building steel, milk lines, water lines, ect.... Problem is, As little as 2 volts is enough to effect a cow.

Allot of the stray voltage can not be traced to the source. Work with the service provider, and get in contact with the county extension agent, or field man where the milk is being shipped to.

And you cannot train the cows to except it, because its a form of torture.

Try to identify the source and fix the problem.

Good luck,

phoenix911

I suspect you will find somebody has gone and dug up the copper rods the power utilities use for there earth grid. they can stretch for miles. You can work out which power station as when the cows cark it they are all pointing toward the power plant (coz the voltage lengthwise is more that acrosswise). If the problem is just dodgy milk production you might have to watch the cows carefully and see which way they look uncomfortable...

You could place two rods in the ground and run a wire between looking for voltage and by moving in a circular direction work out where the voltage derives from.

Or go question your local non-ferrous metals scrap yard people as to who has been in with copper rods!

I can't remember which town in I was driving thru, but here was a guy walking down the street with an armload of copper bus, as if from high power switchgear.

dont have an answer to the cow problem, but i have heard of this problem ever since i was a kid . although recently i stumbled across an article about a fellow who discovered that cows all over the globe seem to mostly position themselves in a north / south , head to rear direction while out in the pasture. i think he kinda stumbled onto this while working on sattelite imagery. i wonder if the amish folk have any home spun remedys out in the barn ?

We came across a similar problem, except that it was a 'tingle' voltage from the water in a hot tub to the ground. In our case the rural customer in question located near the start of a long single phase lateral. The rural subdivision had a common well for a few homes that provided a good return path for the neutral. The effect of the long radial line is that there is a return current in the neutral (it gets "balanced" when it joins back up with the 3phase neutral, assuming it's a fairly well balanced system), and consequently there was a potential difference between the system neutral and the return path through the earth. We unbonded the neutral of the secondary transformer to correct this. If lightning is an issue, there is a device called a "wronk(sp?) reactor" to bond the secondary transformer to ground to protect it. Hope this helps.

Look at this document: http://www.hydroonenetworks.ca/en/customers/farm/strayvoltage/SVSolutionsGuideforElectrical_Contractors.pdf

havlokt@shaw.ca

Was he system installed by KBR .

They have many problems espically in Iraq .