Hello all;

Saw this pole at the current project I am working on - which is not a Bank!
(well, there's a Bank in this Building, but that's not what I am working on ...)

These Images were taken from the Roof of an existing 4 Floor Commercial Office Building - built in 1966.



Image 1: Utility Pole.

Check out how dirty the Insulators are! (the ones with the Yellow Arrows pointing towards are worse than others!)
Looks like there has also been a flash-over situation going on at times. Rains had come through prior to our arrival, which likely washed them off a bit.
It's not clearly seen in the Image, but there's some "Tell-Tale" signs of repeated flash-over on several Insulators.

Along with this, check out what Conductor Material was used for the Primary Feeders + the Underground drop to the Pad Mounted Transformer!
(notice the color?)

One reason for the bright color on everything is shown in this Image below:



Image 2: View Of Local Area.

See the Pacific Ocean in the background? It's no more than ½ Mile to the Beach.
Very beautiful area to work in!

One of the things that was odd to me, was the type of Transformer feeding this Building.
It's a normal Pad Mount Utility owned Animal - as shown in the next Image:



Image 3: Pad Mount Transformer.

The Transformer is owned by SDG&E, and has the "Mad Electricity Shocking Someone" warning labels on it too! (love those labels!).
The Transformer's setup is a 480 VAC 3Ø 3 Wire Grounded Delta.
What's odd (to me) is the way it's Grounded. It appears to be Center Tap Grounded, not Corner Grounded. (I really expected it to be Ungrounded!)

Found 240 VAC to Ground on two Lines, and "More than 240 VAC" on one Line to Ground, as measured with my Wiggy. I expected to find the "usual" Wiggy's response to an Ungrounded system - nothing to Ground, something Line-to-Line.
When the Wiggy responded with a "Solid" buzz, figured I had a Corner Grounded Delta. Found all three Lines had solid measurements to Ground, and no Active System Grounded Conductor is located in the MSB.

Not that this was a problem, just never expected it!

BTW, we are installing new Gas-Turbine Generating equipment (plus panels and a Transformer), for a Co-Generation System at this Building.
Really interresting stuff! I'll add pictures as things progress.

Scott35

Hmm,
1/2 mile from the beach in SDG&E territory. Are you north or south of Camp Pendleton? (Throw me a bone here )
It's hard to see in the picture but are you pointing out that the cables going to the transformer are concentric neutral with corroded copper? (Another bone requested here)

One reason for using 480V center-tap-grounded service is to “skirt” around NEC 230-95 ground-fault-protection. It’s a poor compromise, for you also lose the ability to use ‘slash-rated’ 480Y/277V circuit breakers and 300-volt fuses. The capability for arcing-ground-fault damage compared to 480V grounded-wye service is essentially the same.

Scott,
Cool pictures, there mate!.
Usually we have problems with the linking wires between the insulators and the Primary cut-outs flashing over between phases, where these have been installed with too much slack on them.
I can't help but notice the "High Voltage" signs on the cross-arms in Image 1.
Any one that is close enough to read that label, should know what they are dealing with.

Hello all, and thanks for the replies!
I'll address them accordingly.

Nick;

Nice to see you again!!! Must have been busy lately.


South of Camp Pendleton. A bit West of Miramar. North of Mission Beach / Mission Bay. Off of Torrey Pines Rd.....
Give up?

La Jolla.


Ding!!!
I forgot to make note of this in the message, but the third Yellow Arrow (on the extreme right side), points to the colorful
green oxidation which is common on all exposed conductors.

Bjarney;


I was thinking in this direction, but wasn't sure if it would be a reality! The Service is 1000 Amps rated (at 480 VAC 3Ø
3W).

Trumpy;


No problem about me getting anywhere near this stuff!!! I am actually >30 feet from the pole, with the lens at full zoom. Even
this was too close for me!


Again, thanks to everyone for the replies. Couldn't believe how much built up on the Insulators! One looked like it had a pile of
dirt on it!

See 'ya all soon!

Scott35

Scott,
What I actually meant w/ respect to my comments, was people cimbing poles and finding that there are HV lines on the Top Cross-arms.
Just as a question, Scott, 4 cross-arms down, is that a Earth-Potential Neutral Conductor?.
Is that some form of a clamping device on that wire?.

Mike (Trumpy);


<HOMER SIMPSON>
***DOHHH!!!***
</HOMER SIMPSON>

I am sorry, dude! Thought you were concerned with my proximity!

There's no spikes on this pole, and the Tree's limbs are trimmed off no less than 10 feet above grade - but as you know, this will not stop the most determined Bozos from climbing the pole "Just because It's There!"

Fortunately, there is no outbreak of Clowns climbing 12 KV poles for fun (guess no one has taped such madness and sent it to "Jackass"!). Hope this remains a true statement for many years to follow.

As to the remainimg stuff on this pole:


I believe it's another Utility (this pole is shared Utility).
The lower ones - 3rd and 4th down, are CATV and Telco.
As I remember, the 3rd one down is the Local Cable Utility's Trunk, and the 4th one down is the Telco Utility's Trunk.
(at least, I think this is what you are referring to - the shorter crossarms, which are below the 2nd "High Voltage" set, and fall right under + inline with that Guy Wire which heads towards the "Time/Date Stamp"???)


I am unsure whaddaheck it actually is - or what it's called, but it is something used in conjunction with the "Messenger Guy" (Guy Wire that supports the Cable), and is a mounting base for "Tap Outlets" which are Inline on the Trunk Cable(s).
I do not know the correct term for these things, but it's where the COAX cables to subscribers terminate to the Trunk (for CATV), or where the Customer's drop to the NID (Demarc) terminates into the Trunk (for Telco).
I really need to learn these terms - so any website links or other information from anyone would be greatly appreciated (sp???).

Let me know if the areas I described have something / nothing to do with your reply!


Thanks for the messages, Mike!

Scott35

La Jolla,
Pretty nice area. I was supposed to do the new headquarters for IDEC off Noble and the 805 just a few miles from there. We lost the job though. Don't you work in San Bernardino now? Or did you move companies again?

San Berdoo.... That was quite some time ago!
That option fell through for some reason, so never got out that way.

Whaddya think of that Church on Nobel @ the 5 Fwy? Huge Spires! Great location for Lightning hits to those tall Spires (they are the highest points in the entire area - and the Church is located one of the highest points of the hills!).

Scott35

Hey Scott,
Thanks a heap for your info, mate!.
Most appreciated.
I never even thought of it being a Dual service pole.
One thing I do find strange(compared to here), is the fact that the Primary fuses and the Surge Diverter brackets clip around the cross-arms, where-as, over here, they are bolted through the cross-arm, with Stainless Steel bolts and nuts and huge washers.

Around 415V maybe? Now where have run into that voltage before?

What I believe Scott35 is describing is a three-phase four-wire delta configuration, but at double the voltage of the usual “240/120V 3ø 4W&#8710;” system. See lower left illustration at 6L6.net/localuser/busbar/imag/eei10.distckt.jpg

It has been used in some cases to skirt the NEC 230-95 service-entrance ground-fault protection mandated for ‘1000+ ampere’ 480Y/277V systems. It is the worst combination for a grounded 480V system, because 277-volt overcurrent devices cannot be safely applied, similar to the problematic corner-grounded 480V-delta system, but it still has the potentially disastrous capability of switchgear arcing-ground-fault burndown recognized {and normally protected for by GFP} in 4-wire 480Y/277V solidly-grounded systems.

{The mutant ‘480/240V 3ø 4W&#8710;’ system is used occasionally by some utilities in the US, but should have 3-element metering to correctly register energy use as in other 4-wire solidly-grounded systems—with careful understanding of limitations.}




[This message has been edited by Bjarney (edited 01-06-2004).]

Correct - as Bjarney mentions I was refering to a 3Ø 4 Wire Delta - with Center Tapped winding, of the "Double Voltage" family.

I found 240 VAC on two of the three Phase Lines - as measured L-G, and on one Phase Line, found "More Than 240 VAC to Ground" - and since this smells "Delta-Ish", one could figure the Voltage to Ground on that single Maverick Phase Line to be in the area of 415.68 VAC
(240 × 1.732)

First thing I was thinking when there was a Voltage to Ground measured (with a Wiggy), was a Wye setup - having the Common Star Point Grounded. Finding >240 VAC to Ground on one Phase Line was totally unexpected, and debunked the Wye concept!

This was a nice "Whaddaheck" experience to me, as it was so totally unexpected!
(however, the guy I was working with found this to be of no interest, which really bummed me out!).

Bjarney;

The Image referenced in the last post didn't have "Image Tags" enclosing the URL (as far as I can see).
Let's see if it shows up in this message with tags surrounding it.



If it does not work, maybe you can try something else, enclosing its URL with image tags.

FYI, this looks like:

[img] URL to reference [/img]

Only, do not use any spaces like I have done here (did this to eliminate the BB software from going Berserk trying to figure out that tag!).

Scott35

Ooops on my part... "http://" was incorrectly stripped by me.
http://6l6.net/localuser/busbar/imag/eei10.distckt.jpg

If you copy and paste " 6l6.net/localuser/busbar/imag/eei10.distckt.jpg " into the IE address field it works.

An alternate [color!] version is http://home.att.net/~benmiller/elecsys.htm
"CENTER-TAP GROUNDED DELTA" illustration—second three-phase four-wire configuration




[This message has been edited by Bjarney (edited 01-07-2004).]

Scott,

Okay, it's an optical illusion then, because in the first picture it looks like the trees and the pole are right up on the roof, touching it actually!

Bjarney,
How would you place an EWP to "come up" to this particular pole?.
Given all of the messenger wires.

Maybe drive it up to the roof and approach it from the top? ;-)

[ ? Elevated Work Platform ? ]




[This message has been edited by Bjarney (edited 01-10-2004).]

Whoa!!.
LOL
So there are still people out there that have the same way of thinking as me!.
BTW, Bjarney, sorry 'bout the use of the term EWP, most normal people would call it a Bucket Truck, which it is really!.