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#3700 - 08/27/01 02:51 PM Problems back at the farm
mickky Offline
Member

Registered: 07/22/01
Posts: 48
Loc: toronto
Stumbled upon this site today. Not quite sure how to react, though...Your thoughts?
http://www.strayvoltage.org/stories/index.php3

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#3701 - 08/27/01 05:48 PM Re: Problems back at the farm
sparky Offline
Member

Registered: 10/18/00
Posts: 5545
well I'd say it's a keeper of a bookmark, has a lot of useful information by reasearchers etc...

The less burn of the skin, the more damage to the nerves and the brain," Hooshmand said. "The higher degree of burn is only a sign that the skin is dry and is putting up a big fight. Lucky are the ones who have a lot of skin burn."

I'd think about this...If i could...

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#3702 - 09/02/01 07:27 AM Re: Problems back at the farm
bordew Offline
Member

Registered: 08/27/01
Posts: 155
Loc: Vienna,Ohio, USA
 Quote:
Originally posted by mickky:
Stumbled upon this site today. Not quite sure how to react, though...Your thoughts?
http://www.strayvoltage.org/stories/index.php3


Be careful of this one, this is another shot at more government regulation. Does anyone remember the scare of the high voltage lines causing cancer in residential areas, supposedly even if they pass over head this was supposed to cause serious health risks, accccording to government reports. I would think there would be more of a risk of a downed line than stray electric fields.

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#3703 - 09/02/01 08:51 AM Re: Problems back at the farm
electure Offline

Member

Registered: 12/24/00
Posts: 4226
Loc: Fullerton, CA USA
Mickky,
This is a great site! Just the kind of mad science wierdo stuff I love!

Bordew,
I got knocked nearly out of the boom truck once changing out a ballast in a parking lot pole that had 300KV lines above. The circuit was shut off, but the ballast secondaries still read 98V. (OK, guys. Burn me for not taking out the tester first, yes I was an idiot) There's a health hazard

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#3704 - 09/02/01 08:05 PM Re: Problems back at the farm
mickky Offline
Member

Registered: 07/22/01
Posts: 48
Loc: toronto
 Quote:
Originally posted by electure:
Mickky,
This is a great site! Just the kind of mad science wierdo stuff I love!

Bordew,
I got knocked nearly out of the boom truck once changing out a ballast in a parking lot pole that had 300KV lines above. The circuit was shut off, but the ballast secondaries still read 98V. (OK, guys. Burn me for not taking out the tester first, yes I was an idiot) There's a health hazard

My first reaction was amused,(because of the High tension line non-issue of a few years back)but saddened-these poor people were at the mercy of what, to me, appears to be inadequate ground, or lifted neutral(?)Did they do the work themselves? I can't tell.

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#3705 - 09/25/01 03:06 PM Re: Problems back at the farm
bordew Offline
Member

Registered: 08/27/01
Posts: 155
Loc: Vienna,Ohio, USA
 Quote:
Originally posted by mickky:
 Quote:
Originally posted by electure:
Mickky,
This is a great site! Just the kind of mad science wierdo stuff I love!

Bordew,
I got knocked nearly out of the boom truck once changing out a ballast in a parking lot pole that had 300KV lines above. The circuit was shut off, but the ballast secondaries still read 98V. (OK, guys. Burn me for not taking out the tester first, yes I was an idiot) There's a health hazard

My first reaction was amused,(because of the High tension line non-issue of a few years back)but saddened-these poor people were at the mercy of what, to me, appears to be inadequate ground, or lifted neutral(?)Did they do the work themselves? I can't tell.



Thats exactly my point, we wind up with more regulations, and not all are bad, but for example, the '99 code change where it instructs us to remark a white wire if it is a switch leg. As long as I can remember in this field and thats about 29 years that whit wire in a switch box has always been hot and you return to the switch on the black. Evidently a DIYer was confused about this and got shocked, purely a case of not knowing what you are doing, so what happens they make a code change, beccause of this.
I have never heard of a ballast holding a charge that long, because the time constant is not that significant, but there always that possibility.
When I think of stray voltage, I think of farms, they are the biggest abusers of this. They have a " Maypole " in the middle of the yard where they distribute to all there buildings with three conducctors, and of course they pick up or better yet generate a lot of stray voltage, ground-to-neutral, because of a lot of process piping in the ground, explain why this is happening and they look at you like you are nutz. So they call the power company and the PoCo tries to cover their own butt and install a Neutral blocker at the pole, which of course does nothing to elimate the problem. Milking parlors are notorious for stray voltage.

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#3706 - 09/25/01 03:38 PM Re: Problems back at the farm
NJwirenut Offline
Member

Registered: 09/15/01
Posts: 816
Loc: Bergen County, NJ
Sounds like the ballast circuit was getting charged up via inductive or capacitive coupling from the overhead 300kV line.

I have noticed that line crews often connect temporary grounds to deenergized lines that they are working on, to prevent problems from this kind of coupling (or in case a dispatcher at the substation decides to heat up the line before the work is completed!).
Apparently, when the voltages are high and there are long, parallel runs of cable (such as mulitple levels on a set of poles), the induced voltage in the "dead" line can easily reach hundreds/thousands of volts, depending on humidity and distance between the lines.

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#3707 - 09/26/01 08:04 PM Re: Problems back at the farm
Dallas Offline
Member

Registered: 08/07/01
Posts: 159
Loc: North Salem, IN 46165
 Quote:
Originally posted by NJwirenut:
Sounds like the ballast circuit was getting charged up via inductive or capacitive coupling from the overhead 300kV line.

I have noticed that line crews often connect temporary grounds to deenergized lines that they are working on, to prevent problems from this kind of coupling (or in case a dispatcher at the substation decides to heat up the line before the work is completed!).
Apparently, when the voltages are high and there are long, parallel runs of cable (such as mulitple levels on a set of poles), the induced voltage in the "dead" line can easily reach hundreds/thousands of volts, depending on humidity and distance between the lines.



I've read safety manuals on grid linework that put the reason for the induced voltages on transmission line to wind flowing around the wire creating induced currents.

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#3708 - 09/26/01 10:26 PM Re: Problems back at the farm
Scott35 Offline

Broom Pusher and
Member

Registered: 10/19/00
Posts: 2724
Loc: Anaheim, CA. USA
Makes a lot of sense to me that the Ballast would be producing output voltages!
There's an intense magnetic field cutting across the windings, which varies in intensity and direction [such as AC].
Along with this, there's a Capacitive Coupled circuit, which is common to the source of Induction [the magnetic field] and the earth ground.
This is exactly the same thing as if the Ballast was fed via the lighting circuit.
The distances between the overhead lines [acting as the primary], and the Inductor it's self, makes little difference at high intensities.
FYI: An Impedance matching Transformer, such as used to convert from Coax [75z] cable, to flat twin lead [300z] cable, has a very large separation between the primary and secondary. Separation may be as much as 2", and they are commonly air core.

The Induced Volt-Amperes would not be high enough to drive a Lamp, but could be high enough to cause a leathal shock.
There was probably just enough Volt-Amperes available to drive the meter.
Shorting the inputs/outputs will eliminate the Induced Volt-Amperes.

Must have been a Volt Meter with a relatively high input Impedance [low loading effect]. A common "Wiggy" would probably have shown voltage present only for an instant [like 250 milliseconds], then practically die off - very much similar to measuring voltage to ground on an ungrounded delta with a "Wiggy".

The last 3 wire ungrounded delta I checked voltage to ground on was a 480 volt 3 wire delta. Checked voltage to ground with a high Z meter, and got close to 300 on one phase, upto 500 on anothers.
With the "Wiggy", it acted as if I was charging a Capacitor [hence the Capacitive Coupling circuit]. Wiggy never scaled anywhere past the "120" volt line, but the Neon lamp glowed bright for the first 1/4 second [during charge], then rapidly decayed to a dull - near glowing point.

Just wanted to mention these facts!!!

Thanks to Scott W [electure] for mentioning the potential hazard involving any Induction load device within the proximity of high power transmission lines. We all need to remember this somehow, prior to working these conditions.

Haven't checked the link yet. will do later.

Also, the Linemen will "Short Out" the lines while working on them because even after the line is opened, they remain Capacitively Charged. Also they can become recharged again from other power circuits directly inducing them, or via transformers [similar to electure's Ballast situation].

Scott SET
_________________________
Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

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#3709 - 09/27/01 04:28 PM Re: Problems back at the farm
bordew Offline
Member

Registered: 08/27/01
Posts: 155
Loc: Vienna,Ohio, USA
 Quote:
Originally posted by electure:
Mickky,
This is a great site! Just the kind of mad science wierdo stuff I love!

Bordew,
I got knocked nearly out of the boom truck once changing out a ballast in a parking lot pole that had 300KV lines above. The circuit was shut off, but the ballast secondaries still read 98V. (OK, guys. Burn me for not taking out the tester first, yes I was an idiot) There's a health hazard


That sounds like an induced voltage not stray voltage. Did you visit their site ? One guy claims, ' Lightning came out of my hands ', these are the same people who constantly report UFO sightings, wiht no substantial verification, and now there is some congressional investigations to boot, with our tax dollars footing the bill. The next thing on their agenda is Class action lawsuits, and who do you think will pay that bill, you guessed it, the US Tax payer.
Granted stray voltage exist but there is usually a reason for it.

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