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#112443 - 06/22/01 07:05 PM Broken Cross Beam
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 Quote:
A 19.9KV Delta line is touching a guy wire after a cross beam broke. No arcing, no opening of the OCPD. All guys apear to be bonded to the GC.

I called in to the PoCo immediately, gave the the location and pole #. The guys terminated in a yard across the street, attached first to a telephone pole.

The lower lines are 4160/7200 WYE, and a 120/240V service triplex is visible.

Has it simply changed it to a corner grounded delta 19.9KV?

-Virgil

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#112444 - 06/22/01 07:42 PM Re: Broken Cross Beam
Anonymous
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What are those dark spots on each guy?

My guess is that this guy is not bonded.



Some guys claim to be bonded, but actually aren't; they have no liability insurance at all.


[This message has been edited by Dspark (edited 06-22-2001).]

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#112445 - 06/23/01 03:03 AM Re: Broken Cross Beam
sparky Offline
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Registered: 10/18/00
Posts: 5545
My area has a # of 'condemed' poles still in service, some have held this classification for years. Many times they will go unaddressed until i (or other sparky's) come along to do a service upgrade, then the fertilizer hits the ventilator....

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#112446 - 06/23/01 05:42 AM Re: Broken Cross Beam
sparky66wv Offline
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Registered: 11/17/00
Posts: 2339
Loc: West Virginia
The guys appear to be bonded together on the telephone pole across the street. Please take my word for it; I tried to get a picture of the other pole to prove that the bonds did exist, but my camera sucks.

Not to be nitpicky (consider the source) but a bond differs from liability insurance, but the joke was appreciated anyway...

[This message has been edited by sparky66wv (edited 06-23-2001).]
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-Virgil
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#112447 - 06/23/01 12:05 PM Re: Broken Cross Beam
Anonymous
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But if those are insulators about 4' out on the guys, what then?

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#112448 - 06/23/01 06:12 PM Re: Broken Cross Beam
sparky66wv Offline
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Registered: 11/17/00
Posts: 2339
Loc: West Virginia
Took a closer look today... You're absolutely right. In the sunshine, the fiberglass(?) rods before the turnbuckle became easier to see. The beam had been repaired, but I'm certain nothing else was changed.

I guess that's why they put them there!

Hey, gimme a break... I'm a post-meter guy!
This stuff is outta my league big time...
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-Virgil
Residential/Commercial Inspector
5 Star Inspections
Member IAEI

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#112449 - 06/23/01 06:41 PM Re: Broken Cross Beam
Anonymous
Unregistered


Hey, gimme a break...
Hey, no problem.

Based on your description there were about two possibilities: Either the line was not energized or the guy was not bonded. The latter seemed more likely (especially with that bright yellow sleeve ).

The man who decided to insulate it should get a gold star. And you also should get a star for reporting the damage.

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#112450 - 06/23/01 07:25 PM Re: Broken Cross Beam
sparky66wv Offline
Member

Registered: 11/17/00
Posts: 2339
Loc: West Virginia
Pardon while I digress a little here...

So, an "ungrounded" 19.9 KV Delta still has
11,489 Volts potential to ground...or???

Where does the Grounded Conductor on the subbed 7200/4160 Wye system originate, and how does it relate to the 19.9 KV lines?

How does a corner grounded Delta keep from shorting?

Sorry to be so elementary, but hey, I'm trying to learn more about it here...

Even though I should probably move this to the theory section, I still think it relates to my original question. Excuse my laziness!

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-Virgil
Residential/Commercial Inspector
5 Star Inspections
Member IAEI

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#112451 - 07/21/01 12:16 AM Re: Broken Cross Beam
glenn35 Offline
Member

Registered: 07/21/01
Posts: 48
OK , first off the part that the line is lying on is a fiberglass rod called a "guy strain insulator". And it looks like it has done its job!

Secondly if that is Delta then you are allowed one ground. At least I guess it would be the same for primary as it is for secondaries. Just guessing. All I have ever worked on was WYE when it comes to primary voltage. Unless you consider 2400/4160 primary. I do not.

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#112452 - 07/21/01 06:26 AM Re: Broken Cross Beam
sparky66wv Offline
Member

Registered: 11/17/00
Posts: 2339
Loc: West Virginia
In fairness to my intelligence, I would like to point out that these fiberglass rods are white/grey NOT bright orange or yellow. If they had been orange or yellow, it would have been obvious.

I have heard of corner grounded delta, and was wondering if one could inadvertently ground any leg without things blowing up...

2400/4160? I believe it's 7200/4160, but I could be in err.

[This message has been edited by sparky66wv (edited 07-21-2001).]
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-Virgil
Residential/Commercial Inspector
5 Star Inspections
Member IAEI

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