ECN Forum Forums Photo Discussion Forums Photos for General Discussion Too Close For Comfort!

That must be quite common for the POCO, because I sent in pictures just like this a year or 2 ago. The pole was right up against the building and you could just reach out and touch it.

Bill,
I think the phrase "A picture speaks a thousand words" springs to mind here.
It's amazing how a different angle can change things.
Personally I really don't see anything wrong with this distance.
Of course, if you have people near that like to stand on the edges of buildings and reach out and touch the pretty coloured fuseholders, then you may have a problem on your hands.
Thanks for the extra pic, mate.

That's true, but.......

I've been nearby (on the ground and some distance away) when one of those fuses lets go, and the resulting arc and "boom" would tend to make me not want to be on that roof servicing that A/C unit.

I guessing, based on the side view (thanks, Bill!) that being at the access door for that A/C unit puts you no more than ten feet away from and inline with those fuses.

And I don't think HVAC guys carry proper PPE for the potential (admittedly slightly possible) arc flash hazard. Or for that matter, that they are even aware that a hazard exists.

Food for thought....

edited for spelling

[This message has been edited by mxslick (edited 05-26-2006).]

Regarding those fuses:
I have heard that those expulsion fuses when they blow open, they do so with a hell of a bang and a lot of sparks and " spare parts" going everywhere... makes me not want to park under one or near one with my truck let alone be under one when it happens to " go off".. Is it true these fuses are like little bombs or firecrackers when they open? Just wondering....

The ones in my neighbourhood are the old links in the "door" type cutouts that just fizzle and open and do not make any noise from what I remember...
A.D

I have been on quite a few Projects, where similar situations existed
(pole mounted stuff, waiting to "reach out and touch someone" - in a matter of speaking... ...)

Several setups were H-Racks, but mostly they're single Poles with Pole Mounted Pots, such as in this thread's images.

With the growing trends of those beloved "Scrap-Happy Jokers"; -
of whom, I am referring to those Rocket Scientists that feel a money making career should be both; a profit situation, and an adventure;...
you know, the ones who work so hard at not working... have the philosophy "Why Work for $200.00 a day - in 8 hours, when I can risk my life, and work really hard for $100.00 a day - in 12 hours...
ones who know the Recycling Center's Staff by name...
(ok, enough about those "Ecologically Minded People"; I just love to rant!)

With the growing trends of those beloved "Scrap-Happy Jokers", wonder how long it's going to be before they try to perform "The Great Copper Harvest" on one of those Pots (Transformers)?!

I can almost see it now...

Park the Car / Truck _Right_ Underneath The Pots, go up on the roof, unbolt a Pot from the mount bracket, and it just "falls" right into the Car / Truck.

Imagine, if you will, the Vonage Commercial; where that guy decided to cut down a rather large Pine Tree, and decides to park the car right next to the tree (not so far to walk!) - and, when the tree begins falling towards the car, he tries to grab it - possibly deviating its fall...
LMAO at the Tree-Car Contact!!!

I see the same occurring with the before mentioned Scrap-Happy, Eco-Minded Personnel!

---------------------------------------
Now for something completely different.
---------------------------------------
On the Newer (?) 100 KVA White Transformer
(tagged "56, 72, 24" sounds like a quarterback ...),
I noticed the center bushing is being used.

Does this Transformer's Secondary only have a single Center-Tapped Winding, instead of having a Split-Coil Secondary?

Have seen a few 208Y/120V 3Ø 4 Wire Wye setups here and there, where the Secondary Common was connected to the Center Bushings (as in this thread's images), instead of at the left-side Bushings.

This setup appears to be a 208Y/120V 4 Wire arrangement (300 KVA, if that matters ...).
Doesn't look like a Delta, well at least the Secondary does not look "Delta-Ish"; the Primary looks really triangular to me though...

Back to the close proximity of said Pole vs/ Building:

Some time ago, I posted some images from a Project in La Jolla (the city that Bugs Bunny should have made a left turn at, after turning right at Albuquerque), where the PoCo had a Pole with 12 KV Primary Circuits "Within Reach of A 10' Stick Of EMT" for someone on the roof.

Being that the project was about 1/4 mile from the Ocean, every piece of Metal was extremely oxidized.
The Fuse Cartridges + the cutouts were a lovely green, and the Insulators had a deep buildup of dirt.

That Pole was mounted like right against the Building!

There are many "H-Racks" around here which are "Just a Hop, Skip and a Jump Away From The Roof", and for some strange coincidental reasons, the Roof Mounted HVAC Equipment is _ALWAYS_ placed right there too!
It's the oddest thing!

(BTW: "H-Rack" = certain PoCo Pole / Framing arrangement, used to set Transformers on, in-lieu of Transformers hung on Pole mounted Brackets).

Anyone know whazzup with the Common derived from the Center-Most Bushing - i.e. Single Coil Secondary???

Scott35

edited for spelling and plot-holes in story.

[This message has been edited by Scott35 (edited 05-26-2006).]

Adam,
Yes, expulsion-type fuses are designed to provide enough force upon fusing, to knock the top of the fuse link out of the holder and allow the fuse carrier to drop down and hang in it's hinge at the bottom of the fuse carrier, ready for the PoCo faultsman to replace it.
Admittedly they do go off with a rather pronounced bang, but bear in mind the amount of energy flowing through that fuse-link before it ruptures, that has to be dissipated.

I have heard that those fuses are filled with some sort of chemical which, when ignited by the melting fuse element, generates large amounts of a gas which helps to quench the arc. The "bang" they give off is a result of the rapid expansion of the gases produced.

Thank you for the information!!!
I will keep it in mind should I hear a loud bang and see one of those cutouts fallen open somewhere... ( preferably not the ones between my place and the substation

A.D

***EL~BUMPO!!!***



Scott35

BTW, anyone know if the Transformer with the White enclosure has a single secondary winding, which is "Actually" Center-Tapped?

Me...