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1st Class Husker
08-22-2008, 10:50 PM
See if anyone and help out on this one!

Had a call in a single phase underground hog confinement, workers were getting shocked when spraying the pens down with the hotsy sprayer! Did some checking and found that going from metal building to ground it measured 7 volts! Measured from ground to elbow arrestor and measured 1.3 amps!
We first thought it was our side, so we started opening the neutrals and dumping all phases and reenergizing them one by one, NO Change!
There are 8 hog barns so we dumped the disconnects and one by one started picking the load back up. By the time all 8 barns were disconnected we had .7 volts with leaving the wells still on. Another kicker is when the emergency generator kicks in the stray voltage immediately goes away!

what is everyones thoughts!

I guessed in the generator transfer switch!

BigClive
08-23-2008, 05:39 AM
Is the frame of the metal building in good electrical contact with the ground? (earth rod?)

Is the spray washer properly grounded? It could be IT that's giving shocks to ground.

CPOPE
08-23-2008, 06:39 AM
See if anyone and help out on this one!

Had a call in a single phase underground hog confinement, workers were getting shocked when spraying the pens down with the hotsy sprayer! Did some checking and found that going from metal building to ground it measured 7 volts! Measured from ground to elbow arrestor and measured 1.3 amps!
We first thought it was our side, so we started opening the neutrals and dumping all phases and reenergizing them one by one, NO Change!
There are 8 hog barns so we dumped the disconnects and one by one started picking the load back up. By the time all 8 barns were disconnected we had .7 volts with leaving the wells still on. Another kicker is when the emergency generator kicks in the stray voltage immediately goes away!

what is everyones thoughts!

I guessed in the generator transfer switch!

http://www.mrec.org/pubs/svd.pdf

Check out this definition and NEC code requirement

Equipotential Plane. An area where wire mesh or other conductive elements are embedded in or placed under concrete, bonded to all metal structures and fixed nonelectrical equipment that may become energized, and connected to the electrical grounding system to prevent a difference in voltage from developing within the plane

547.10 Equipotential Planes and Bonding of Equipotential Planes.
The installation and bonding of equipotential planes shall comply with 547.10(A) and (B). For the purposes of this section, the term livestock shall not include poultry.
(A) Where Required. Equipotential planes shall be installed where required in (A)(1) and (A)(2).
(1) Indoors. Equipotential planes shall be installed in confinement areas with concrete floors where metallic equipment is located that may become energized and is accessible to livestock.
(2) Outdoors. Equipotential planes shall be installed in concrete slabs where metallic equipment is located that may become energized and is accessible to livestock.
The equipotential plane shall encompass the area where the livestock stands while accessing metallic equipment that may become energized.

JAKE
08-24-2008, 10:44 AM
are yall on a grounded wye system?

one of the last ones i ran across at a dairy barn fed by a single phase service they had a radio plugged into a non polarized plug backwards and that was causing the stray voltage they couldnt get the cows into the milk barn they wouldnt come up the ramp since thats where the differnce in potential was.

the one before that i had was 4 services upstream from another dairy at a trailer house they had an old single phase 110v well pump that had a shorted pump and since it wasnt properly grounded it was causing stray voltage all the way down to the dairy.


do they have any thing before the transfer switch? or is it at the service entrance? sounds like they have the generator grounded better than the service or the generator is taking care of the issue.

we have been putting ronk blockers in where we have had the stray voltage issues to isolate the neutral and cover our side since most of theese farmers and dairymen wont get someone out there to do it right, the only time they will is after they have had a brush with death from electricity <- just makes me think of the dutch dairymen has his burned handprints on a 480 delta disconnect....

Trbl639
08-30-2008, 12:24 AM
we had a similar situation on a swimming pool at a house...floated the neutral on the pot that fed it (only customer on that pot) and it cured it!!!

King
11-28-2008, 06:53 PM
I got a similar call a ladies horses were getting shocked when they stepped off the rubber mat in their stalls onto concrete in the barn. While I was asking the lady when it seemed to happen I leaned up against her truck and got shocked. It seems the truck had an AC block heater on it that had malfunctioned. Current was running back on the ground wire of the plug and causing the concrete to have voltage on it.

Troubleman730
01-26-2009, 11:03 PM
This happens a lot in the sandy soil of N.J. We found that swimming pools create a better ground than the system neutral. Thus causing all the inbalance from the system to discharge through the Swimming pool, or wet pump area. Bonding the entire area sometimes helps.

CPOPE
02-01-2009, 03:38 AM
Hydro jolt hits students
Sparks $15M inspection
Last Updated: 31st January 2009, 4:43am

Several students being shocked by stray voltage has prompted Toronto Hydro to spend $15 million to mobilize 600 workers to work round-the-clock inspecting its aging street-level infrastructure.

Three to five students from Regent Park/Duke of York Junior Public school were zapped but uninjured Thursday, prompting Hydro president and CEO David O'Brien to announce the mobilization -- the largest in the utility's history -- at a hastily called news conference yesterday.

It's the first time a child has been struck by stray voltage and comes after two dogs were electrocuted and several were shocked in the last two months.

"Parents are just going to have to be careful until we can get it done," O'Brien said. "If you see (handwells), don't step on them."

Adults are getting zapped, too, Talia Russo said.

The 28-year-old was walking on Spadina Ave. earlier this month with her younger brother when they felt a shock on the northwest corner of Wellington St., she said.

"It was strong enough to make me scream 'Ow!' " the 5-foot-1 Russo said yesterday, comparing it to stepping on something sharp but feeling it all the way to her knees.

'I'M SCARED'

"They have to do something about it if children and adults are feeling it -- I'm scared to walk anywhere in this city."

Russo said she mentioned it to a Toronto Hydro worker on the street later that day.

Regent Park residents were upset to hear about children getting jolted on their streets.

"That is a real problem and I think an investigation is needed to find out what's going on," Malcolm Babbage, 31, said. "This is occurring all the time and now we've got to worry about our kids stepping in the wrong place?"

'VERY SAFE'

Mary Watson, 43, a mother of three, said she wants to know what's being done to make sure other handwells are not going to be a problem.

But O'Brien stressed Toronto's streets "are very safe," and the utility is addressing the stray voltage aggressively. "We're going to get it fixed.

"We are taking our workforce off everything else they do and this is all they are going to be doing until they get it fixed."

On Thursday, several students told teachers they received a shock near the corner of Dundas and Sumach Sts., Toronto District School Board officials said.

A letter sent to parents from the principal stated staff determined that each of the students had stepped on a handwell.

TDSB spokesman Kelly Baker said the children appeared uninjured but cautioned parents to take them to their doctor just in case.

About five blocks from the school, a hydro crew found a handwell with stray voltage.

The utility had already allocated $10 million to sweep for stray voltage and replace metal handwells after the electrocutions of a German shepherd in November and a Labradoodle this month.

O'Brien said in the wake of the incident involving kids, the utility opted for a blitz, costing an extra $5 million.

"This is going to cost an awful lot of money but you can't put a price on a life," O'Brien told the Sun.

Avid
02-04-2009, 04:26 PM
Myself and two other JL were sent out to troubleshoot stay voltage on 4800 delta. A lady would get a jolt getting out of her swimming pool, and grabbing the metal hand rail. We measured 2.x volts there.

Long story short, the neighbor's house (only other one at the same pot) didn't have their panel attached to a ground rod, and the cable company had attached a ground to top of their meter box. At that wire to ground - 56 volts! Disconnect the cable line and it went away completely. Remove the cable ground wire and again it went away, so we left it off and reported both issues to engineering.

We were there for a few hours to figure that one out! I never heard what they ended up doing, or whether grounding their panel caused it to bleed off.

CPOPE
02-06-2009, 01:43 AM
(Posted Date: Monday, February 2, 2009)
Dusko Avramovic says his family is “still in shock” over the loss of their beloved dog Mrak, a Labrador-poodle mix.
Dusko Avramovic knows his family is struggling to keep going after the loss of a very close friend.

On Jan. 13, his 25-year-old son Darjan was walking their Labrador-poodle mix, Mrak, in the Keele and Annette Sts. area when the dog unexpectedly dropped to the ground.

“(My son) was panicked when he was trying to call me,” Avramovic recalled. “I left here to run there, and I found (Mrak) on the sidewalk motionless.

“When I actually tried to hold him with my arm, I felt a shock,” he added. “It surprised me, out comes a shock like this. And then I figured out he stepped on that plate.”

The incident sent a tremor of emotion through the family.

“How are we coping? Terrible,” Avramovic said, sounding distraught. “The kids: when they wake up, they’re crying first, then they go to university. When they come back, they’re crying again.

“It’s unbelievable.”

Disbelief shifted to irritation when asked what Toronto Hydro should do with stray voltage, believed to be the culprit behind Mrak’s death.

In November, a German Shepherd suffered the same fate while out for a walk with its owner near Keele and Dundas St. West.

“In this case, we’re talking about dogs,” said Avramovic. “It’s not going to change until something worse.

“What if you bent to pick up something and you touched a plate?” he added. “Waiting by the bus stop, people taking change from their pockets, how many times have they dropped something? If you try and pick it up and touch a plate, you’ll get shocked and get killed.”

In response, Toronto Hydro is moving forward with a citywide sweep to detect any stray voltage.

“We’re treating the matter very seriously,” Hydro spokesperson Denise Attallah said. “It’s a safety concern for us, so we’re starting our citywide customer campaign.”

The utility established a hotline on Jan. 26 and is urging anyone concerned about errant current to call 416-222-3773.

In addition to the hotline, Toronto Hydro will replace metal handwells with non-conductive ones, splitting $10 million between the project and the safety sweep. Stray voltage is electricity present on a structure or surface that shouldn’t be energized.

How safely electricity is transported from one source to another has triggered concern in Councillor Bill Saundercook, who serves on Toronto Hydro’s board of directors.

“Toronto Hydro . . . (is) scanning the entire city with this infrared technology to look for the stray current that’s culprit in these situations,” he said.

Saundercook said people are at low-risk of being shocked because of rubber-soled footwear.

However, he said the use of salt and the pooling of water during winter contribute to a “toxic mixture” for the animals.

“I had asked Toronto Hydro and city transportation to explore the use of sand only,” he said. “That way, you might eliminate the pooling aspect of it. They replied that they’d thought salt was very minimally contributing to the problem.

“They wanted to attack the problem at its root and not at the surface.”

Still, Avramovic wants the city to change its safety codes for electricity, especially after two more dogs were zapped in Yorkville. They were unharmed.

“They have to ground something,” he said. “In the house, you have a metal box for the switches (and) the box has to be grounded. That’s the same thing.”

Whatever is done is unfortunately too late for the family’s beloved Mrak.

“I’m still in shock,” Avramovic said. “Wherever I turn around the house, there are memories of a beautiful dog — I could say person, friend.

“Not only ours, but the whole neighbourhood’s

CPOPE
02-14-2009, 05:30 AM
Published Friday, February 13, 2009

A corroded electrical connection is being blamed for the stray current that injured a dog in downtown Hudson on the night of Feb. 6.

The exposed wire was in an electrical box beneath a Second Street sidewalk at Locust Street, according to Craig Kraemer, a journeyman wireman for B & B Electric who helped fix the problem Monday morning, Feb. 9.

Kraemer said the exposed wire likely conducted electricity into the metal box and the wet concrete surrounding it.

A five-year-old black Labrador retriever suffered burns on her paws, stomach and chest when she was shocked while crossing Second Street with her owner, Scott Hawkins of New Richmond.

Hawkins, a Hudson real estate agent, was returning to his car at about 8:15 p.m. after having attended the Hot Air Affair parade and fireworks with his girlfriend and her children.

He said Cady began to yelp and bite at one of her back feet when they were about three feet from the curb on the east side of Second Street.

Hawkins said the dog lay howling in pain for about a minute before he was able to remove her metal collar and chain. He said he could feel the electricity going through the dog as he removed the collar.

Cady lost control of her bowels during the ordeal and was bleeding from her feet.

Hudson Public Works and Parks Director Tom Zeuli, who also was downtown for the Hot Air Affair celebration, learned of electrical problem minutes after the dog was injured.

Zeuli quickly went to the control panel for the streetlights in that area of the downtown and turned off the electricity.

“I knew exactly which circuit to close down after talking to the police,” Zeuli said in a phone call Friday morning. “The situation was handled within minutes.”

The streetlights along Second Street from Walnut to Vine streets remained off the rest of the weekend.

B & B Electric, a Hudson company, was called about the problem early Monday morning and had it fixed by 8 a.m., Zeuli said.

Kraemer said wires in the pole boxes expand and contract as streetlights come on and go off in the winter months.

“So there is a little bit of rubbing that could occur on parts of the pole boxes,” he said.

The rubbing can wear off the wire’s protective plastic coating and the vinyl rubberized tape that covers connections.

Kraemer said he couldn’t be sure how the stray voltage was conducted because the system was de-energized when he investigated the problem Monday morning.

“So I don’t know how much current was bleeding off,” he added. “It could have been low voltage, around 10 volts, up to 60, 70, 80 volts.”

Kraemer said he told Zeuli and Mark Loughney of the city Public Works Department that they should visually check all of the pole boxes in the city to make sure there are no other exposed wires. The pole boxes are typically at intersections that have electrical lines passing underneath the street, he said.

Zeuli said Friday morning that Loughney was in the process of carrying out the inspection suggested by Kraemer.

“We’re going to do what we have to. We’re investigating things right now,” he said.

Zeuli said the city has been “pretty progressive” in replacing old streetlights. New streetlights were recently installed on Crest View Drive and Carmichael Road, and the downtown lights were replaced just a few years ago, he said.

The dampness and temperature extremes in this part of the world, as well as the salt and chemicals used to combat ice, can cause problems with electrical wiring, Zeuli said.

Hudson Mayor Dean Knudson said in a telephone call Wednesday that people don’t need to be afraid about walking their dogs on downtown sidewalks.

“It has been fixed,” he said of the problem that occurred at Second and Locust streets.

Hawkins told a Twin Cities newspaper that the city of Hudson will pay a $400 bill from the veterinary clinic that treated his dog.

He reportedly said he doesn’t plan to sue the city unless Cady has long-term injuries. The dog is on antibiotics and pain medication and is expected to make a full recovery, the newspaper reported.

up2it
03-26-2009, 08:55 PM
See if anyone and help out on this one!

Had a call in a single phase underground hog confinement, workers were getting shocked when spraying the pens down with the hotsy sprayer! Did some checking and found that going from metal building to ground it measured 7 volts! Measured from ground to elbow arrestor and measured 1.3 amps!
We first thought it was our side, so we started opening the neutrals and dumping all phases and reenergizing them one by one, NO Change!
There are 8 hog barns so we dumped the disconnects and one by one started picking the load back up. By the time all 8 barns were disconnected we had .7 volts with leaving the wells still on. Another kicker is when the emergency generator kicks in the stray voltage immediately goes away!

what is everyones thoughts!

I guessed in the generator transfer switch!
First of all get ride of that meter and get an old simpson style meter. Shut down all the wells and see where you stand. If there are other well in the same water aguaffer it could be the problem. 98% of the time it come from the customer side. If you can't find it , I still think you can, get a Ronk blocker> It won't fix the problem but they won't see it any more.

Divemaster
03-27-2009, 08:08 PM
Apparently you have a distribution high voltage feeding this installation since you have elbow arrestoers. You might very well have a bad arrester that hasn't blown yet. I found a bad elbow arrester by getting knocked on my can one day hooking up a locator.

CPOPE
06-24-2009, 04:18 AM
Jun 22, 2009 (St. Louis Post-Dispatch - McClatchy-Tribune Information Services via COMTEX) -- JEFFERSON COUNTY -- Signs warning, "Spring Lake closed until further notice," have been posted around the Summerset subdivision in southern Jefferson County for the second time in three years.

Another person says she was shocked by an electrical current in the lake that no one seems able to explain.

But this time, nobody died.
Three years ago, four teens jumped off a dock into Spring Lake just south of De Soto. Shortly after hitting the water, the teens became immobilized by an electric current. Nic Harbison, then 16, drowned. Morgan Milfeld and Tim Fitzpatrick, both then 15, had to be resuscitated. The fourth was pulled to safety.

A jury in March found AmerenUE liable and said the utility company had to pay $2.3 million to the teens' families. The settlement and verdict brought a sense of vindication to Tracy and Ginger Jones, who owned the dock from which the teens had jumped. Some residents had believed faulty wiring on their property was to blame; Ameren's attorneys also pointed the finger at them during the trial.

The couple spent most of the last three years away from their lake house and just moved back over Memorial Day weekend.

That's when the mysterious electrical current struck again. This time, it happened directly across the lake, at Jim Theel's dock.

Shawna Theel, 25, was dangling her feet in the water off her family's dock beside her daughter, Ariana, 5. The little girl begged her to hold her closer to the water so she could feed the catfish some dog food.

But Theel, still leery of the lake, said no.

"I can't imagine what would have happened if I would have let her go near that water," she said.

Minutes later, Theel grabbed a metal ladder to pull herself up. One foot was still in the water, she said, and it felt like something had "bit her foot off." She said she was thrown back on the dock.

"I thought I was going to look at my foot and not see any toes," she said.

But they were still there, cramping and tingling. She grabbed her daughter and ran back to the house.

Within an hour, her father brought his voltage meter to the dock and got a reading of 7 volts from the water.

He said he has taken his meter to the lake every day since Nic Harbison died. Some of his neighbors invite him to take readings from their docks, too. Readings vary, but often the meter registers 4 to 5 volts.

Until he sees a reading of less than 1 volt, Theel said he won't believe the lake is safe.

He called Ameren UE to report his daughter's shock last month. Crews promptly responded.

Spokesman Tim Fox said Ameren was still investigating the cause of Shawna Theel's jolt. "We don't have the final results yet," he said.

Meanwhile, the utility has been working to replace and reroute underground cables in the subdivision to improve service. On May 19, Fox said, Ameren de-energized a cable that ran below the lake. That cable was identified at trial as a possible source of stray voltage.

Jim Theel and Jones believe the underwater cable is only part of the problem.

At trial, attorneys debated the results of a study that showed other underground cables that run around the lake and supply power to homes had corroded. Expert witnesses offered mixed opinions on whether the voltage escaping from those cables could cause a jolt powerful enough to immobilize a swimmer.

The National Electrical Safety Code does not specify a safe level for stray voltage, but some studies have suggested anything above 2 volts can cause a problem to a swimmer, said Donald Johnson, a Wyoming-based licensed professional engineer who testified as an expert witness on behalf of the Jones family at trial.

The Theel and Jones families said they hope the Ameren crews working in the subdivision now are going to replace all of the corroded cables.

Fox said he is unsure whether all the cables are being replaced.

Theel said residents just want to find the problem and get it fixed.

"People are worried about their property values, and they don't want to hear that we can't swim in the lake," he said. "They don't want to hear the truth because sometimes it hurts." On Wednesday last week, Theel put his voltage meter in the water off his dock. It was about 1 p.m. The temperature was near 90 degrees. The ground was saturated from a few days of heavy rain. Air conditioners around the lake were buzzing.

Theel got his highest reading to date: 9.1 volts.
Two days later, he returned to register a reading of 10.5 volts.

To see more of the St. Louis Post-Dispatch,

Edge
06-24-2009, 10:00 PM
I remember running into a similar problem a long time ago...it was on a uniground y system...ground rod return... the problem was they didn't have a ground rod they had bonded to the sewer line...well over the years the sewer pipe had been abandoned (they hooked up to county water/sewer) and eventually it rotted out... after a while they had no return... I wonder if this could be similar...
bad return = fugged up current and you get shocks because it's trying to "return"...
interesting problem...

for what it's worth....

Edge

CPOPE
06-28-2009, 09:29 AM
THE DAILY NEWS
Posted 1 day ago

It's another victory for 73-year-old Dover farmer Lee Montgomery.

But the celebration is bittersweet.

The former dairy farmer is pleased the province has finally recognized ground current pollution. New legislation will take effect in mid-September that will contribute to the health and safety of livestock and human beings.

"I'm very happy,'' said Montgomery, who claims stray voltage ruined his life and took the life of his wife, Donna.

Montgomery has spent the past 30 years trying to make the government aware of the seriousness of the problem.

His first breakthrough came in 2006 with a private member's bill by Lambton-Kent-Middlesex MPP Marie Van Bommel.

The bill received all-party support at second reading.

That was the first time he was able to celebrate victory.

Last week the Ontario Energy Board announced amendments to the distribution system code in relation to farm stray voltage.

Montgomery said it ensures that electricity to farm customers is of a quality that does not unduly impact the health and safety of a livestock operation.

He said the Ontario Electrical Authority has been named as the third party mediator in case there is a dispute case over mitigation.

Montgomery claims his farm was affected by stray voltage from an Ontario Hydro substation on Highway 40, south of North Maple Mall.

He said the day the substation was shut down his electrical problems ceased.

Montgomery credited Barry Fraser, a consultant and former Kent agricultural representative, as well as Van Bommel, for helping win the battle.

Fraser said the new amendments lower the threshold level for mitigation from 10 V to 0.5 V-a factor of 20.

"This is the lowest of any jurisdiction in Canada and probably North America,'' he said.

Fraser said the ruling "vindicates'' Montgomery, who was chastised at the time as a trouble maker.

Montgomery said his problems began in the early 1970s.

"It cost me the life of my wife, the loss of my dairy herd, the loss of my milk quota and I was forced to sell a 100-acre farm,'' he said.

In the 1970s and 80s, Montgomery traveled throughout Canada and the U. S. showing his award-winning Holstein cows.

Montgomery claims that stray voltage is not only an Ontario problem, but is one that faces people and farm animals throughout North America.

The new amendments call for fully-trained and qualified investigators under the Occupational Health and Safety Act.

Fraser said the new amendments will ensure that electricity to farm customers is of a quality that does not unduly impact health and safety on livestock operation, especially dairy farms.

"It permits the accurate determination of the contribution from the distribution system to total measured farm stray voltage at animal contact points like the feet and mouth,'' he said.

http://www.chathamdailynews.ca/ArticleDisplay.aspx?e=1632476 (http://www.chathamdailynews.ca/ArticleDisplay.aspx?e=1632476)
Article ID# 1632476

CPOPE
08-25-2009, 09:21 PM
Voltage scare costs Hydro $14.4M
Utility seeks to charge customers to offset bill

Toronto Hydro's city-wide inspections and repairs in the wake of last winter's stray-voltage scare cost the company $14.4 million – and the utility wants customers to foot part of the tab.

The company has asked the Ontario Energy Board for permission to charge every residential customer an extra 68 cents per month this year to help offset the spike, spokeswoman Tanya Bruckmueller said. The increase, which would be retroactive to January, would raise about $5 million from the 605,500 residential customers.

The fee hike would decrease after the initial year, she said.

Meanwhile, Hydro has two contact-voltage detection trucks working on a full-time basis. The vehicles were introduced as a temporary measure in November, when a dog was electrocuted after stepping on a short-circuited hydro plate.

The utility ramped up its repair services at the end of January after a second dog was killed and five young students reported being zapped in Regent Park.

Over the next month, Toronto Hydro's 600 employees worked around the clock to scan and check the city's 155,000 light poles and hand wells.

The initial estimated cost of $6 million quickly ballooned. In the end, 228 cases of high levels of contact voltage were discovered.

"Torontonians need to feel safe when they're coming down the street," said Blair Peberdy, Toronto Hydro's vice-president.

"We had two dogs killed, tragically, and reports of a child being shocked. There was no hesitation and we're firmly convinced that (the repairs and new detection services are) the right thing."

Hydro's preventative program also includes a 24-hour hotline for reporting suspect hot spots and a public awareness campaign, expected to launch in October.

CPOPE
01-06-2010, 08:46 PM
Another dog shocked by hydro plate in TorontoKenyon Wallace and David Shum, National Post and Global News: Wednesday, January 6, 2010 4:36 PM

A Toronto Hydro worker uses instruments to test a hydro pole and the plate below it after dogs were shocked by walking on the plates.
http://a123.g.akamai.net/f/123/41524/1d/www.globaltoronto.com/Another+shocked+hydro+plate/2411722/2411745.bin?size=sw380nws
Stray voltage scare cost $14-million to fix, Toronto Hydro revealsAnother dog has been shocked by a metal hydro plate in Toronto.

The incident occurred Monday night near the intersection of Danforth and Donlands Avenues when the black lab was out for a walk with its owner and stepped on a sidewalk hydro plate.

Bar owner Jimmy Tzortzouklis says he saw the dog, a chocolate labrador retriever named Shroeder, drop to the ground.

"All of a sudden the dog started shaking, was paralyzed here," he said. "I thought the dog had a seizure or something."

Aldrian Bisa works at a veterinary clinic down the street. He rushed to help the 100-pound dog and felt the current himself.

"The first time I tried to lift the dog, I said, 'there's an electric shock,'" Bisa said.

The dog was taken inside the clinic, where doctors determined it wasn't seriously hurt.

Toronto Hydro spent close to $10-million last year on inspections and repairs to tens of thousands of sidewalk hydro plates across the city last year after several dogs were shocked after stepping on the plates.

On Jan. 13, 2009, a five-year-old Labradoodle named Mrak was electrocuted after stepping on a metal plate at the base of a hydro pole. About a week later, two more dogs being walked by their owner in Yorkville were shocked by metal plates.

Toronto Hydro has warned that stray electricity in the plates may be a problem in the winter months because of aging infrastructure.

But that's no consolation to dog owners.

Stinger
04-17-2010, 10:18 AM
In Vermont and in wisconsin they have stray voltage arrestors on the secondary neutral. This will prevent any stray voltage from the stantions or milking devices. 1/2v of stray voltage will stop a cow from milking. I learned that from a Green Mountain power lineman. Found it kind of interesting.

BigClive
04-17-2010, 11:48 AM
1/2v of stray voltage will stop a cow from milking. I learned that from a Green Mountain power lineman. Found it kind of interesting.

So what voltage is require for Latte? :D

CPOPE
04-18-2010, 12:15 AM
Saturday 27 March 2010 08:10
Dairy farmers could improve milk production and quality by keeping a close check on stray electricity voltage in their milking parlours and collecting yards.

And, according to New Zealand service technician Tim McDonald, mistakes as simple as using tape to connect an electric fence to collecting yard steel can generate enough voltage to upset cows when they are about to be milked.

During a recent visit to the UK, Mr McDonald tested for stray voltage at 23 dairy farms. "I didn't find one that was completely clear so, when you interpret those numbers on a national level, you could say most farms in the UK have a problem,'' he says.

Stray electricity occurs when voltage is unable to make its way to the main earthing system and a natural path for voltage to travel back to earth in a milking parlour is the steelwork. Water, which is used in large volumes in the parlour, exacerbates the problem.

"When five standings are affected by stray voltage and you add water to the mix, it will double the affected area,'' says Mr McDonald, Corkhill Systems.

Research shows cows are sensitive to just 0.5V and this in turn impacts on production and somatic cell counts. Stray voltage results in cows receiving a tingle or a mild shock that disturbs their normal behaviour.

"When a cow is nervous she won't let go of her milk so it stays in the udder until the next milking. By the time the cow releases that milk it has been in the udder for several hours and is not of the best quality, so cell count levels will be affected.''Herdsman Simon Musson of Vaynor Farm, Narberth, Pembrokeshire milks a spring-calving herd and suspected there was a problem with stray voltage when cows were mucking more than usual. "They were nervous before they came into the parlour and, after having the equipment tested, we now know this was caused by voltage from an electric fence running through the steel barriers in the collecting yard."

He hadn't picked up on the problems because, although cows and humans can be similarly sensitive to electric current, cows are more susceptible to stray voltage because they have much lower body impedances.

Mr Musson followed the advice he was given by Mr McDonald and replaced the tape securing the fence with timber fencing. The problem has now been eliminated.


Mr McDonald says farmers should avoid having an electric fence active while milking and instead should install a relay system which switches the power off at milking times. An electric fence controller should never be installed in or near a milking parlour and electric fences should always have a separate earth at least 20m from the mains earth.

The biggest problems Mr McDonald has come across are in rotary parlours, due to the many variable-speed drives associated with this type of system and the positioning of the milk pump on the platform. "The drives are not suitable for use in a parlour unless they are correctly fitted,'' he says.

The worst case he has come across is a reading of 14V in an 80-point rotary parlour which had an incorrect drive. The herd's cell count reading was a phenomenal 650,000 cells/100ml. "We fitted the correct drive and the cell counts plummeted,'' says Mr McDonald.

The usual source of stray voltage is faulty wiring. This could be due to cracked insulation, incorrect grounding or overloaded circuits. But new wiring incorrectly installed could be a possible source too.

Problems can also arise from milk float stems that protrude into the milk vessel. Each time the pump starts up it creates a spike of electricity. "It may be a case of replacing it with a variable speed pump which runs all the time, slowing down or speeding up according to how much milk is going through the system so there isn't a spike," says Mr McDonald.

In some cases, stray voltage can also be brought in through power lines.
http://www.fwi.co.uk/assets/getasset.aspx?itemid=5225054
Testing the system to identify the sources means the problem can easily be rectified, says Mr McDonald. "The solutions to dealing with stray voltage are so often simple and easily done."

Symptoms of stray voltage
• Excessive or unusual nervousness and excessive movement

• Reluctance to enter or eagerness to leave the milking parlour

• Increased frequency of defecation and/or urination in the milking parlour

• Reluctance to consume water

• Poor milk let-down

• Increased milking time

• Lowered milk production

• Increased somatic cell counts and incidence of clinical mastitis

CPOPE
12-02-2010, 08:04 PM
Sam, a 6-year-old German shorthair pointer, was killed last week when he stepped on this plate (right) next to a streetlight on Queen Anne Avenue.

Seattle officials worked to reassure people that its streetlight system is safe, after a dog was electrocuted and another injured on an electrical vault cover in Queen Anne last week.

A pinched wire and faulty grounding of four streetlights caused the dangerous energizing of the metal sidewalk covers, authorities said. A private developer had paid a contractor to install the lights, according to the city, but how the faulty work passed the city's inspection process remained unclear.

Seattle City Light said the city's transportation department was in charge of inspecting the project. The Department of Transportation said City Light had final responsibility.

After repairing the wiring, city officials said they were investigating other potentially hazardous lights in the city. But they were unable to offer any specifics on what research methods they were using.

They also pronounced the Queen Anne incident as unique, despite its ongoing investigation and despite other reports from dog owners with similar experiences elsewhere in the city.

"We want the public to be assured that this was an isolated incident," City Light superintendent Jorge Carrasco said in a blog post this week.

"We are researching our records to determine whether there are similar lights elsewhere in our system. If we find there are, they will be inspected and any necessary repairs will be made immediately."

Fatal incident

It wasn't until Thanksgiving that the problems emerged with the lights, located on Queen Anne Avenue North, between Galer and Garfield streets in front of the Gilbert Building.

Lisa McKibbin had been walking her dog, Sam, a 6-year-old German shorthair pointer, when the dog stepped on a plate near one of the lights, yelped and collapsed. He died in front of her.

A week later, accountability for what happened remained a mystery. The Gilbert's developer, Easthom Investments, had paid for the design and installation of the decorative pedestrian lamps, but said the city had been responsible for inspecting and energizing them.

Suzanne Hartman, a spokesman with Seattle City Light, said the city's Department of Transportation was in charge of the permitting and inspection process, because the lights were part of the street right-of-way.

"Once the contractor is finished, SDOT does the sign-off and tells City Light we're ready to energize these lights," she said.

But Richard Sheridan, a spokesman for SDOT, said the project didn't sound like something for which the department would issue a permit. He was less clear about inspections, said he would check on it, and deferred questions back to City Light.

"They're ultimately responsible for it," he said.

Hartman said city crews discovered the pinched wire on Monday. It had been in the streetlight closest to the plate that killed the dog. Its s protective coating had worn away.

That caused electricity to course through the light pole and into at least two underground electrical vaults, energizing them and the metal sidewalk plates that cover them.

If the vaults had been properly grounded -- as required now and back in 2006 -- the exposed wire would not have been a problem, Hartman said. But the vaults' connections had not been grounded as required, and a key lug was missing from the light with the pinched wire.

Hartman said some older city lights - installed 40 to 50 years ago - also don't have the modern grounding required today. But she said they are not hazardous.

"They are not going to be the problem, unless there's a problem like the pinched wire," she said.

News of McKibbin's experience spurred a few other dog owners in the city to come forward with similar stories. John McDowell said he had been walking his dog, Oslo, in the same Queen Anne area the day before Thanksgiving, when his dog let out a "bloodcurdling, screaming yelp" and fell to the ground with convulsions.

"He had fallen, like he had no legs," McDowell said.

McDowell, who owns the clothing store Oslo's near the problematic lights, had also stepped on the plate - south of the one that killed Sam - and said the current tore through the rubber sole of one of his boots.

On the Queen Anne View blog, a dog owner named Marla described how her dog had yelped and "flew backwards" seemingly in shock, after peeing on a light post in Belltown.

The owner said she had complained to City Light and got no response. She wrote, "I wonder if it will take a child getting hurt/dying to get them to fix these?"

Another dog owner commented on the blog that her cocker spaniel had also been injured after stepping on metal plate in West Seattle, which caused it to yelp and writhe in pain.

City Light did not immediately return a call for comment on those reports. Hartman said the plate that killed Sam gave off an estimated 90 volts. The one that injured Oslo emitted 30 to 60 volts, she said.

McKibbin said that Carrasco, the department's superintendent, had personally called her to apologize. But what she really wanted was an exact accounting of the circumstances that led to her dog's death.

"No one's explained anything to me," said McKibbin, who has started a blog dedicated to Sam, whom she described as "my beloved best buddy who I will miss forever."

"I do not want this to happen to a person, child, another animal, a best friend," she said. "I would like to see the city do something to improve our public safety."http://www.seattlepi.com/local/431065_dogshock.html?source=mypi