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#127981 - 04/05/02 11:38 AM Grounding electrode conductor in kindorf
Elzappr Offline
Member

Registered: 12/20/01
Posts: 273
Loc: Oregon
How long would a piece of strut (kindorf, unistrut..) have to be, when partially enclosing a grounding electrode conductor, to increase the grounding impedance to, say, 1 Ohm? Is the air gap so large that for all practical purposes the impedance is not affected by the strut?

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#127982 - 04/05/02 05:18 PM Re: Grounding electrode conductor in kindorf
Chris Rudolph Offline
Member

Registered: 05/01/01
Posts: 160
Loc: Winter Park,Fl USA
What are the characteristics of Kindorf?

Chris

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#127983 - 04/05/02 07:51 PM Re: Grounding electrode conductor in kindorf
Elzappr Offline
Member

Registered: 12/20/01
Posts: 273
Loc: Oregon
Don't know. I would start by assuming that it is just a mild steel channel about 3/32" thick with dimensions of 1-7/8" for the three sides, and an air gap of maybe 1".

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#127984 - 04/17/02 06:47 PM Re: Grounding electrode conductor in kindorf
Redsy Offline
Member

Registered: 03/28/01
Posts: 2138
Loc: Bucks County PA
I believe that since the strut doesn't totally encircle the conductor there is no choking effect at all.

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#127985 - 04/20/02 10:23 AM Re: Grounding electrode conductor in kindorf
Elzappr Offline
Member

Registered: 12/20/01
Posts: 273
Loc: Oregon
That was my initial assumption too. But then I got to thinking that since there IS a complete magnetic loop (though with a huge air gap that creates a reluctance nearly equivalent to just air) then there might be some way that there would be a choking effect. I just don't know how to figure the inductive reactance based on a magnetic circuit's characteristics..except for the text book examples for constructing filter coils. I don't know if there has to be eddy current paths along with the magnetic loops in order for there to be a large inductive reactance. Logic informs me that since there can be inductive reactance for even a straight piece of wire, then partially enclosing it in strut would certainly increase that reactance..but by how much?

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