Really large induced ground fault currents

[Paul Mathews]

Check this out:
http://www.powerlinesystems.ca/documentation/CaseStudy_Sept07_MysteryCurrent.pdf

This was brought to my attention by John Woodgate.
Paul Mathews

 

[Tim Shoppa]

Check this out:http://www.powerlinesystems.ca/documentation/CaseStudy_Sept07_Mystery...

This was brought to my attention by John Woodgate.
Paul Mathews

The generic term for these faults is "stray current", and although the
article seems to consider just a few tens of amps of stray current as
a big deal, in the industry where I work in we don't really notice
these "stray currents" until they reach hundreds or thousands of amps.
It's kinda sad, but the threshold seems to be front-page-of-the-
Washington-Post!

Tim.

 

[Adrian Jansen]

Check this out:
http://www.powerlinesystems.ca/documentation/CaseStudy_Sept07_MysteryCurrent.pdf

This was brought to my attention by John Woodgate.
Paul Mathews

Sounds like a good source of "free" power to me.

--
Regards,

Adrian Jansen adrianjansen at internode dot on dot net
Design Engineer J & K Micro Systems
Microcomputer solutions for industrial control
Note reply address is invalid, convert address above to machine form.

 

[Mark]

Sounds like a good source of "free" power to me.

--
Regards,

Adrian Jansen           adrianjansen at internode dot on dot net
Design Engineer         J & K Micro Systems
Microcomputer solutions for industrial control
Note reply address is invalid, convert address above to machine form.

Could this really be true?

Any physics types out there that can calulate how strong the magnetic
field would have to be to create that kind of induced power __in free
air__.

I would think that any ferrious metal objects and audio systems in the
area would be humming a tune and CRT displays would be dancing to it.

Mark

 

[Tim Shoppa]

Sounds like a good source of "free" power to me.

When you have stray current flowing through ground that also happens
to contain natural gas pipelines and storage tanks, and they notice it
because all of their metal is corroding far faster than it used to, it
doesn't seem so "free" no more!

Tim.

 

[Tim Shoppa]

Could this really be true?

Any physics types out there that can calulate how strong the magnetic
field would have to be to create that kind of induced power __in free
air__.

I would think that any ferrious metal objects and audio systems in the
area would be humming a tune and CRT displays would be dancing to it.

To give you an idea of the environment I work in, color CRT displays
every few minutes twist and turn funny colors. And I'm five to ten
feet from the rather small (few square feet) current loop. Of course
when the current is 10,000Amps... .

The gotcha in the article was that there were two loops both of very
large area in the original wire layout. If either loop had small area
then there wouldn't have been such a problem. Every so often I run
across a consumer product where there's large loops and make them
especially susceptible to 60Hz (or n*60Hz in my office from the
multiphase rectifiers) hum but for the most part the professionally
produced stuff knows to eliminate the loops.

Tim.

 

[**THE-RFI-EMI-GUY**]

The generic term for these faults is "stray current", and although the
article seems to consider just a few tens of amps of stray current as
a big deal, in the industry where I work in we don't really notice
these "stray currents" until they reach hundreds or thousands of amps.
It's kinda sad, but the threshold seems to be front-page-of-the-
Washington-Post!

Tim.

I dunno, I think the power worked out to about 700 watts. Thats a lot of
uncontrolled power to be dissipating from one point off your house siding.

--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

 

[neon]

This will never happen in CALIFORNIA a loss of this kind of power would have been detected as loss. or theft of power. Even dirty insulators can rob transmission power tat is why mission energy periodecaly wash them to remove grits or loss of power.