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#104556 03/13/03 04:47 AM
Joined: Oct 2000
Posts: 2,749
Member
WebSparky removed this old switchgear this week!

Front view of main disconnect switches for 240V 3-phase delta. This is the first means of disconnection for the complex.

See if you can find the "fusible links" in the following photos.

[Linked Image from grafixbynix.com]

[Linked Image from grafixbynix.com]

[Linked Image from grafixbynix.com]

[Linked Image from grafixbynix.com]

[Linked Image from grafixbynix.com]

[Linked Image from grafixbynix.com]


More to follow ......




[This message has been edited by Joe Tedesco (edited 03-13-2003).]


Joe Tedesco, NEC Consultant
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#104557 03/13/03 04:57 AM
Joined: Oct 2000
Posts: 2,749
Member
[Linked Image from grafixbynix.com]

[Linked Image from grafixbynix.com]

[Linked Image from grafixbynix.com]

[Linked Image from grafixbynix.com]




[This message has been edited by Joe Tedesco (edited 03-13-2003).]


Joe Tedesco, NEC Consultant
#104558 03/13/03 11:12 AM
Joined: May 2001
Posts: 552
T
Member
I've never seen anything like that,and hope I never run across anything like it. [Linked Image]


Donnie
#104559 03/13/03 11:54 AM
Joined: Aug 2002
Posts: 1,691
S
Member
Joe, was that a trick question? I sure don't see any fuses...or at least any I would recognize. I guess they're inside the switch boxes with the knifeswitch on the sides, right?

I wouldn't mind hooking up that awesome bare-bones three-pole knife switch to something at home!! Too bad I don't have a 220-volt high-power air conditioner. JUST KIDDING!!! [Linked Image] [Linked Image]

[This message has been edited by SvenNYC (edited 03-13-2003).]

#104560 03/13/03 02:18 PM
Joined: Nov 2002
Posts: 134
R
Member
Looks like that disconnect on the top left of the third photo is above 6 feet. shame! shame!

The working space in front of the disconnect panels looks to be a violation.

The 3M corporation thanks you for the demonstration of the isulating qualities of their tape.

This stuff is classic. I hope it was saved for the antique as well as for converstational interests. Back in the good old days when safety was in the eye of the beholder.

Just how old is that transformer? Any PCB concerns?

Any photos of the new installation available?

RSlater,
RSmike

#104561 03/13/03 08:02 PM
Joined: Apr 2002
Posts: 7,381
Likes: 7
Member
The fusible links are "in-line" type, covered with tape, and if ya look hard enough, you can make them out in the pic Joe posted. At the right and left sides of the transformer.
Have to go now, be back ASAP
John


John
#104562 03/13/03 08:06 PM
Joined: Nov 2000
Posts: 2,148
R
Member
I would expect that the transformer is way too old to have PCB oil. I don't think that was used before the late 50s.
Don


Don(resqcapt19)
#104563 03/13/03 08:07 PM
Joined: Apr 2002
Posts: 2,527
B
Moderator
It’s easy to forget that at one time deadfront gear was not used. Those are some great photos of some hideous equipment.

Joe, were these pics taken on the North-American continent?

The place also looks like it would rate in the top ten for EPA-Superfund sites. I can’t imagine that someone buying into/signing off an “upgrade” consisting of no more than stencils and a tablespoon of white paint. All that’s missing is a broomstick with a nail for “safe” switching.

Are the interrupting ratings for this stuff NEGATIVE numbers?

#104564 03/13/03 09:00 PM
Joined: Feb 2003
Posts: 138
W
Member
Hi Guys,

This old switchgear has been in use since 1920! It was powered off a high voltage transformer (Y-DELTA windings, 11,400V / 250V delta, ungrounded on the load side) across the driveway next to the building.

We received a service call Monday at 9am. about partial power loss at the complex.
Since we have performed service work there before and the complex has high voltage through out, the two "old farts" were dispatched to see what the problem was.

We arrived and met the maintenance electrician with the keys to the vault. We checked the high voltage meter on the outside of the vault and the phase indicators said that we lost "B" phase.
The customer phoned the POCO and they dispatched a crew.

Upon their arrival, we entered the vault. They checked the 25A 11,400V fuses and found "B" was blown.

Since there was no way to drop the load on the secondaries, (those knife switches were protected by a block wall located 21" directly in front of them)the POCO had to transfer other customers off of that grid to a temporary grid leaving this customer the only one live.

After 2 hours time, POCO returned. This time they brought 2 supervisors, two high votage crews and a transformer tech to test the transformer when it was down for the fuse replacement. The transformer has a date on it of 1908.

Because NO ONE of us present was willing to step in and throw those knife switches, even with hot gloves and a hot stick, the POCO had to drop the grid remotely via computer contol.

Once they did, the testing began. Since we could not effectively isolate the tramsformer secondaries, (because NO ONE was willing to throw the switches closed if we opened them now)the test was canceled after several inspections by us and the POCO crews.

The crew replaced the high voltage fuse. They ordered all of us back to a safe distance (duh!)and switched the transformer back on line via live cell phone person to person conversation and computer control downtown.

When the switch was made, the overhead service drop to the next building with the knife switches began to dance up and down and make a terrible noise. The cell phone conversation was "shut it down, shut it down, shut it down".

Houston, we have a problem.

Since there were 3 separate overhead drops to the building and only one of them was dancing, we cut the wires and taped them off.

The POCO then gave the command to re-energize the grid again. This time, no problem. Two out of the three were good.

As you look at the knife switches, the one on the top right was the one with the short.
Notice the sixth photo. There is a "U" shaped thingy bolted between the line side of the switch and the load side. Those are the "fusable links". They are made of a composit of copper and lead and have no rating markings on them. They still look fine!

Yesterday after installing a temporary service drop and reconnecting all of the loads you see in the photos, (23 wire splices) we reenergized the complex.

I am glad my company has taken the time and expence to train all of the field employees in the OSHA 30 Safety class. Not that we were dumb before that, but having the proper training and knowledge most likely saved a few lives durring this service call.

The complex has contracted with us to install two new 480V services to replace the old one here.

The way we originally got this client was through a service call back in the summer when one of their other high voltage swicthgear blew them of the grid and several other clients. Because of our professionalism and our unwillingness to compromise safety standards during this service call, they naturally called us first when they went down.

Yes, safety does pay. It's just like anything else of value, it takes an investment.

I will follow up with photos of the new switchgear.

Dave


Dave
#104565 03/14/03 12:33 AM
Joined: Aug 2002
Posts: 1,691
S
Member
OK, I see the fuse links now. It's the things that I first mistook for some sort of cable bracket....

What's going to happen to those knife switches? Museum?

Someone should set up an exhibit of stuff like that....lord knows there's museums of all kind of weird things now! [Linked Image]

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