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#94834 08/16/05 06:55 AM
Joined: Dec 2004
Posts: 1,064
D
Member
Roger, wouldn't the steel pipe have a higher resistance than the copper wire?

Wouldn't this cause more fault current to be placed in the wire than the pipe. 2 parralell resistors with different values?


Dnk.......

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#94835 08/16/05 12:13 PM
Joined: Jul 2004
Posts: 9,928
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G
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Dnk, I suppose people will always argue about how nuch current flows in the pipe vs the wire but the leading edge of the fault flows on the skin and there is a lot of skin on the pipe. (or the whole issue of whether it becomes a choke)
All we know from experience is the system of wire in a pipe, bonded at both ends, works better than simply being bonded at one end.


Greg Fretwell
#94836 08/16/05 12:17 PM
Joined: Aug 2003
Posts: 1,374
R
Moderator
According to the IEEE, the inductive choke create during a high frequency event can be as much as 97% on a raceway that is not bonded.


Ryan Jackson,
Salt Lake City
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