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I object to the remark that my article was patent nonsense. It may not be an in depth scientific discussion of the problems with the electric transmission system in the United States but it is certainly a verifiable and truthful overview. Stray Voltage is a very serious issue in any area of our country that has a number of dairy farms. I am in Wisconsin, the "dairy state" and I know that dairy farmers are battling this issue continually in addition to the issue of the power of the utility companies to prevent the dairy farmers from finding satisfaction.
In the US, electricity is sent out on transmission lines. All electricity sent out, must return to the substation it came from. Electricity will follow the path of least resistance, and our utility companies commonly use the earth to provide that path. Anything in the way of that path may be affected by the electricity as it returns. Dairy farms are often wet (water, manure) and the cows are in direct contact with the earth. They also frequently have a lot of metal work, another electrical conductor. So, if a dairy farm is between the substation and a transformer, they may be inundated with the current as it returns to the substation.
All lactating and or/gestating mammals are affected by stress. Stress causes hormonal changes that may prevent the animal from producing milk or even having a normal or natural labor and delivery. Stray voltage has been documented as causing stress. Some of the ways it may cause stress are to cause electric shocks, stress, distress, or discomfort when in contact with watering devices.
Dairy (milk) is a huge industry in the USA. Stray Voltage causes thousands if not millions of dollars of lost revenue to dairy farmers. However, Utility companies are also very powerful financially and they would have to acknowledge culpability, and then change the way they transmit electricity to solve this issue.
Waiting4rain 01:44, 31 May 2007 (UTC)
Also, although I'm not an expert on the US, I doubt that it's correct that they use earth return for <emph>transmission</emph> although they may use it for distribution. It's also not correct to say that earth return is not used in Europe; it is used; albeit only rarely in very remote areas. Dontdoit 02:17, 31 May 2007 (UTC)
Okay, so this article has many serious problems. Here's a nitpick (by comparison to the larger problems): Currently it says that some farm in Michigan got measured "stray voltage" of "below one milliampere". Since when did anyone start measuring voltages in amperes ? I find it hard to believe the US supreme court would commit such a physics 101 error. Is there a reference ? --Eivind Kjørstad 15:09, 14 October 2007 (UTC)
Did she die in 2004 or 2005? Both dates are mentioned in this entry. Pelle79 (talk) 13:38, 19 November 2008 (UTC)
Cool. Put a light bulb and a buzzer on every single metal object that might get energized. You can get a patent for the darndest things - and you don't even need to hire a draftsman! For the cost of putting these gadgets on, you could put in a big horking copper bonding strap and actually *prevent* the problem instead of just hanging a light on it. pat2pdf.org is *so* useful... --Wtshymanski (talk) 17:03, 7 February 2009 (UTC)
I finally found a good source which explains the problem.[1] This is a study for the Ontario Energy Board (marked, amusingly, "Private Information - Not to be Disclosed without the consent of the Ontario Energy Board", but it's on their web site.) The fundamental problem is that the neutral wire in 3-phase distribution systems is not only grounded at more than one point (see ground loop), the neutral on the high side of the transformer is tied to the neutral on the low side. So some fraction of the neutral current will travel through the ground, there can be a potential difference between grounding points, and some of that potential makes it across the distribution transformer. If the load on each phase is balanced, the neutral current disappears, but when the load is unbalanced, there will be neutral current and voltage differences. Ways to measure and deal with the problem are discussed. --John Nagle (talk) 17:21, 4 May 2010 (UTC)
This article does raise some good points, particularly in the arena of agriculture facilities. However, consider the following comments: First, the notion that electricity follows the path of least resistance is mostly true. Because the neutral (return path) in North America is bonded with the ground, return current will use the ground as a return path as well. A bonded neutral is required by the NEC to provide a safe, stable electrical network.
Second, voltage and amperage are not interchangeable terms (as noted in the article that stray voltage can be measured in milliamps). Stray voltage should be more correctly called leakage current. Current returns to the source, not voltage.
And lastly, stray voltage cannot be measured accurately with a voltmeter. A voltmeter measures the potential difference between two points. The most often test conducted measures voltage between a building structure and a reference rod. Where the reference rod is placed (i.e. what type of soil, proximity to a utility ground, proximity to a building, resistance of the rod) can result in widely varying figures. The only way to measure for leakage current is with an ammeter to measure the differential between what power is being consumed and what is returning to the source.
This is an informative article on a subject that is poorly understood by many "experts". -- Danmessina4516 (talk) 13:27, 21 July 2010 (UTC)
I edited this section to remove several incorrect statements. To start, "induced" stray voltage most often does not refer to current induced per Faraday's Law, but rather to false positive readings given by capacitive test devices. Induced current can be a shock hazard on long fences running underneath and parallel to transmission lines, but this not the understood context of this article.[1], [2] I also briefly detailed techniques used by those in the stray voltage detection and mitigation business to distinguish "induced" voltage from voltage measured between a real source and ground. —Preceding unsigned comment added by PrazanPS (talk • contribs) 16:10, 2 August 2010 (UTC)
References
Recently, I posted some new material and appreciate the feedback. Some quick points: the IEEE draft definitions are available on the working group website, already cited at the end of the article. I'll add a reference. I agree more information is needed on the pen detectors and e-field detectors. I plan to add this in the future, as well as a separate article on contact voltage. I have two suggestions to make this article better. First, I think the terminology discussion should be right up front. Stray voltage is that, like "smart grid" or other buzzwords, means very different things to different people and this article should address that up front. The IEEE defs are not the only ones; there are others by NEETRAC and by nearly every state commission that has tackled the issue. Perhaps more of these definitions should also be cited. Nevertheless, definition comes first in an encyclopedia in my opinion. Second, I think the "stray voltage on power systems" section ought to be called "stray voltage phenomena" since it is essentially a list of very different phenomena that are frequently placed under the "stray voltage" tent. In fact, elevated neutral voltage in the agricultural context is the real stray voltage and these other conditions are similar but different. In a perfect world, they'd all have their own separate words but language is only as precise as its usage. Feedback and discussion on either of these two issues is appreciated. —Preceding unsigned comment added by PrazanPS (talk • contribs) 14:35, 10 August 2010 (UTC)
My experience is limited, but my Fluke pen won't see 125 V DC or 250 V DC, in actual tests. At least one model of "volt pen" isn't going to detect DC. --Wtshymanski (talk) 21:57, 23 August 2010 (UTC)
It has been proposed by someone that Phantom voltage and Stray voltage be merged.
A suggestion has been made to portray the effect of current flow throught the soil from a malfunctioning HV item, E.G. case of a step down transformer used in a electrical distribution substation. If the diagram could explain visually, in simple terms, the logarithmic relationship between distance and current flow through soil.
Like the electrical field strength given off by an R.F. antenna (aerial), the current falls at an inverse square ratio with distance, (as light does from a single point source). For the purposes of the diagram this works in our favo(u)r. A person close the source of stray voltage (the transformer case), the voltage gradient here is so steep as to be fatal. (>50 ma across the heart).
So as to maintain technical credibility, we cannot use underground cable feed into this transformer. The presence of an equipotential cable sheath (to the soil) ) would prevent much stray voltage occuring. One suggestion put forward is to include a graph underneath the picture to visually relate distance and voltage pressure.
This representaion will allow dotted lines to be connected to the ground areas above (in the drawing) and a simple visual relationship will then be observed by the reader.
Use of overhead poles for the incoming (11,000v (u.k.)) and the outgoing (240v /110v), would allow the concrete block, and the transformer on it, to be isolated from the CPC (earth) of the power grid. If a cable connect(x)ion could be added to show that the protective fence around the transformer is equipotentially bonded to both incoming and outgoing (CPC) earths, then the visual image will appear technically correct.
So, to recap, two poles, one ring fence (with open gate), one transformer, 4 people at varying points of the potential gradient, one bringing an external (a water hose has been suggested) into the area, which has the effect of bringing another point of low potential into the area bounded by the fence. help would be appreciated with the necessary line drawings needed. (pole carrying three wires in/out, transformer on base). Francis E Williams (talk) 11:35, 4 December 2010 (UTC)
I did my best to clean up and consolidate the rather confusing discussion of the definitions of "stray voltage". But it appears that there is a fundamental difference between the 2005 IEEE draft proposal and common usage. Does anybody have any updates since then, or useful insights? Reify-tech (talk) 22:56, 2 June 2011 (UTC)
any cases? — Preceding unsigned comment added by 173.62.160.246 (talk) 00:54, 14 April 2017 (UTC)
In the first image/figure/diagram of this article, its caption says "A fallen power conductor from a transmission line forces current through the earth [...]" While I understand that phrase as saying that current travels from the transmission lines to the earth, my question is: at which point does the current return to the electrical grid (power system)?
If it's not returning, then are you saying that AC current can flow in open circuits? --Alej27 (talk) 05:44, 13 November 2020 (UTC)