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Bad CT Cabinet

Posted By: Admin

Bad CT Cabinet - 01/30/06 12:41 AM

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Hi, I am an Electrician in Roanoke Virginia. I have a 3 Phase 120/208 system in a building I am working on for my company. Our local Power Company subbed out another company to wire their end of the CTs. It has taken them 5 days to get this far, but I am glad they did not energize it. This is a 1600 Amp Service - my work on top, Power Company coming in on bottom. This is just unbelievable.

When the sub was confronted about what he had done he really thought he did nothing wrong and even said this is how he was taught to do it in West Virginia.

Look closely at his neutrals, and what you can't see is that in the Xfmr each pipe full of wire is made to a phase so you see B,O,Y,N in a ring here it is all made to A, or B, or C in the Xfmr. I just could not believe it.

The Power Company who had hired them made them fix it and I made them ring out the wires to make sure everything was the way it needed to be, but the guy really did not know what he was doing and as for the Power Company, they are going to question what terminations have been made all over and under the city. This guy was the lead termination guy for his crew and has done a lot of work for our Power Company.

- (no name given)
[Linked Image]

[This message has been edited by Webmaster (edited 01-29-2006).]
Posted By: JAKEE

Re: Bad CT Cabinet - 01/30/06 01:18 AM

Sorry about the no name. I want to make a correction. That company has done alot of work for the local power company not just the crew doing this work.
Posted By: Dnkldorf

Re: Bad CT Cabinet - 01/30/06 02:14 AM

(jaw hanging down in disbelief)


Unbelieveable.....


Dnk..
Posted By: Roger

Re: Bad CT Cabinet - 01/30/06 02:26 AM

What Dnk said!!! [Linked Image]

Jakee, welcome to the forum.

Roger
Posted By: BigJohn

Re: Bad CT Cabinet - 01/30/06 02:34 AM

Let me see if I understand this:

Each pipe containes parallels for a single phase? I.e.: first pipe, A phase. Second pipe, B phase, etc.?

And the guy terminating the cables through the CTs basically created a bunch of dead-short-circuits by connecting one cable from each phase to the same bus?

But here's the trick: Why in the world did whoever installed the cables run a neutral with each pipe? If I was the guy terminating this job, I might just as soon see that and think that each pipe was supposed to contain all three phases plus a neutral. Or were the cables and terminations all done by the same fellow?

-John
Posted By: frenchelectrican

Re: Bad CT Cabinet - 01/30/06 02:40 AM

the other thing the POCO did goof up major time if you look at the CT doughnuts and the wire colors if reading for metering why they go all 3 phase for each CT that will cancled the current reading very effective.

the only way to get the correct reading on CT is have each phase for CT doughnuts that way the meter will read it correct.
i am suprised how they do that

Merci. Marc
Posted By: Tesla

Re: Bad CT Cabinet - 01/30/06 03:09 AM

Cute how our man jumps from high voltage colors to low voltage colors...and NO XFMR....

This priceless photo is so hairball....

It belongs forever in the ECN archive.
Posted By: mahlere

Re: Bad CT Cabinet - 01/30/06 03:13 AM

what kind of conduits coming in from the xfrmr? look to be rigid. Didn't think you could separate the phases in metal conduits.
Posted By: Radar

Re: Bad CT Cabinet - 01/30/06 04:20 AM

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why they go all 3 phase for each CT that will cancled the current reading very effective


That would be OK with me, if I were paying the power bill.
Posted By: electure

Re: Bad CT Cabinet - 01/30/06 04:24 AM

If there are an AØ, a BØ, and a CØ in each of those incoming conduits, I've got some customers that would just love to have this guy hook up their services.
Posted By: RODALCO

Re: Bad CT Cabinet - 01/30/06 09:29 AM

What a mess !!

Besides of wiring completely wrong, It looks like instant fireworks here, if each conduit represents a phase each.
Also its undersized for 1600 Amps anyway.

Then it's a fire hazard in on this wooden panel.
CT's supposed to be in a sealable metal enclosure.

Very poor protection on these, I think PT fuses wiring.( red orange grey ) A fault on these will evaporate the latter, there the fuses are not mounted nearby the point of supply.
Posted By: Ryan_J

Re: Bad CT Cabinet - 01/30/06 02:20 PM

No bonding either [Linked Image]
Posted By: pauluk

Re: Bad CT Cabinet - 01/30/06 03:18 PM

Am I interpreting this correctly? All the cables in the first conduit are connected to the xfmr A-phase, all in the second to B-phase, and so on?

How on earth could he think that's right? [Linked Image]




[This message has been edited by pauluk (edited 01-30-2006).]
Posted By: Larry Fine

Re: Bad CT Cabinet - 01/30/06 04:00 PM

This is scary! This is what separates mechanics from electricians.

I don't even see locknuts on the bottom conduits.
Posted By: wa2ise

Re: Bad CT Cabinet - 01/30/06 05:33 PM

If he was consistant with the color codes on the wires, it looks like he did not separate each phase in its own conduit. But each current transformer will only see a difference of source and return currents, like a giant GFCI. That would make for very low power bills [Linked Image] And this guy does work for the POCO? (I assume that these transformers are for measuring power consumption for billing?).

Or is it that that he wired each conduit and current transformer so they see only one phase, ignoring his color codes? Then there are dead shorts between phases at the terminals in the upper parts of the picture, where the red and blue coded wires connect?

[This message has been edited by wa2ise (edited 01-30-2006).]
Posted By: John Crighton

Re: Bad CT Cabinet - 01/30/06 08:41 PM

Larry, I see no locknuts, either, and no bushing on the 4th conduit. It was just too close to the middle conduit to thread anything onto it. Poor supervision during the initial conduit placement, I suppose.

That's the sort of thing that makes me furious -- it would have been trivial to place the conduits correctly in the first place had someone paid even a little attention. Since they didn't, it becomes impossible to make it right later. Like a bird turd hitting a snowy slope and starting an avalanche.

So, all those cables in the 5th (rightmost) conduit must be connected to the transformer neutral lug, and that's why they don't pass through the CTs on their way to shorting everything the hell together. There's just so much wrong here, it's amazing.
Posted By: JAKEE

Re: Bad CT Cabinet - 01/31/06 12:55 AM

Well the first thing to say is the CT cabinet is ok it is open right now to take the picture. The ridged conduit coming up in the can is tied to PVC in ground all the way to the xfmr. And the xfmr is bonded correctly, and there is a grounding bar on the right of the CT cabinet that the meter ground #6 solid is going to, you just can't see it becuase of the door being open. this CT cabinet is also located inside the electric room.For those who thought it was outside.

Glad to be here, thank you for for the welcome
Posted By: electure

Re: Bad CT Cabinet - 01/31/06 01:02 AM

JAKEE,
Which one of the wrong ways were the conductors connectred?
Dead Short, or Cheap Metering?
Posted By: JAKEE

Re: Bad CT Cabinet - 01/31/06 01:08 AM

electure it is both
Posted By: kiwi

Re: Bad CT Cabinet - 01/31/06 10:19 AM

How flammable is that wood its all mounted on ?

Thats the worst CT chamber I've ever seen.

Is this work subject to inspection ? How did it pass ?
Posted By: RSmike

Re: Bad CT Cabinet - 01/31/06 05:26 PM

Am I reading this right???

The wires in each conduit (the ones identified with different colored tape - DUH!) are tied to one single termination point for each phase in the transformer. You can't be serious. As in it would be an instant phase to phase and phase to neutral fault if turned on!!!!

Got a photo of the other end.

Let's not even talk about the CTs.

RSReally,
RSmike
Posted By: mamills

Re: Bad CT Cabinet - 01/31/06 09:10 PM

The question I have about the low voltage colors (black, red, blue - 120/208) for the load (EC)side, and the high voltage colors (brown, orange, yellow - 277/480, I assume) for the line (POCO) side, is this: If these same high voltage colors appear on the conductors at the transformer location, what is the possiblility that this service will accidentally be provided with high voltage [Linked Image]?

Mike (mamills)

[This message has been edited by mamills (edited 01-31-2006).]
Posted By: yaktx

Re: Bad CT Cabinet - 02/01/06 03:35 AM

The phase-taping here reminds me of the Daffy Duck cartoon where he burys treasure and marks it with an X. When he comes back, Bugs has inundated the surrounding area with Xs. Thufferin' thuccotash! I've been thabotaged!

Might as well put every color of phase tape on every wire.
Posted By: Lostazhell

Re: Bad CT Cabinet - 02/02/06 01:49 AM

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If these same high voltage colors appear on the conductors at the transformer location, what is the possiblility that this service will accidentally be provided with high voltage


Pucker factor times # of darwin candidates on that sub crew divided by 1600A³ = Not Likely... Once energized, the transformer will have blasted off and landed on the White House lawn [Linked Image]

Funny, over here in CA, the utility subs I've come across were all very well trained and professional personnel.. I'm sure there's a few loose screws both here and there, but I'd be inclined to think utilities would be more "C.Y.A" conscious!
Posted By: Steve Miller

Re: Bad CT Cabinet - 02/02/06 11:34 AM

This gives me an idea ... my electric bill will be going down quite a bit now [Linked Image]
Posted By: HotLine1

Re: Bad CT Cabinet - 02/02/06 10:33 PM

To add further insult, if possible....a mess like this would never fly here in NJ. (At least the 'northern' and 'central' parts of the state.

John
Posted By: JAKEE

Re: Bad CT Cabinet - 02/06/06 02:58 AM

The wood is legal by local code it is what was spec. for the power co. and yes it had to be inspected for my end the low voltage colors side. I passed it with flying colors. Then this guy hooked up this way on the bottom. The xfmr is 120/208 outside I checked it my self it is just taped wrong the guy did not know what he was doing. And the wood is fire rated.
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