Relocating a dry-type transformer - Contractor Talk - Professional Construction and Remodeling Forum

Magnettica · 09-18-2007, 05:45 PM

Here is a recent job my partner and I did. We were called to do a few things after a wall had been taken down and some equipment needed to be relocated. This is a packaging warehouse on the peninsula of Bayonne, New Jersey.

Here, we had to move this 75kva transformer, relocate the 1" emt feeding the transformer, and trim-out the 2" flexible conduit that contained 2/0 copper feeders to a 200 amp (208Y/120V) main breaker panel. The primary side was fed with #3 copper at 480V.

I thought you guys would appreciate seeing the hack work the previous electrician did when he originally wired this transformer. The lugs were upgraded to 250MCM type.

Now the old wiring has been removed and the transformer moved up against the wall to it's permanent position.

Here's a better shot of the whole project. Note the 1" pipe on the left flapping in the breeze until we extended it to a new 8x8x4 pullbox. The 1" pipe from the tranny to the pullbox was installed using beam clamps and "cowboy" clamps. That 1" emt is a bitch to bend!!

Here's that pullbox location.

Finally, the end of the day when all power was restored.

The inside of the transformer. The bonding jumper is located inside the panel. #4 copper to building steel.

D'oh! No yellow tape!

JohnJ0906 · 09-18-2007, 05:54 PM

In the 2nd picture from the top, did the original guy trim strands from the wire to get it to fit under the lug?

It kinda looks that way, but it's a little hard to tell.

Magnettica · 09-18-2007, 06:00 PM

Yup! I actually used to work for an EC and we used trim the aluminum from a brand new 200 amp service entrance cable (SE) so that the maroon crimps would fit on the conductor. He said "make sure the customer doesn't see the single strands on the ground." No, I'm not kidding.

I uploaded these pics to a smaller pixel setting. Forgot to change the preferences from the other day.

Btw, John, NYY needs to sweep 'em this week.

JohnJ0906 · 09-18-2007, 06:19 PM

Quote:

Originally Posted by Magnettica

Btw, John, NYY needs to sweep 'em this week.

If you need wins, you are at the right place.

Magnettica · 09-18-2007, 08:06 PM

God knows the Jets sure couldn't get it done!

Sparky Joe · 09-18-2007, 09:26 PM

So why are you running 2/0 for 200 amps? or did you correct that?
Did you space the transformer at least 6" from the wall?
Did you bolt down that pallet? Why not take it off the pallet and make a more permanent appearance?
What's the GEC for inside the transformer, you said you bonded in the panel?
And I don't think I see an EGC in that flex?

Celtic · 09-18-2007, 10:10 PM

Quote:

Originally Posted by Sparky Joe

So why are you running 2/0 for 200 amps? or did you correct that?
Did you space the transformer at least 6" from the wall?
Did you bolt down that pallet? Why not take it off the pallet and make a more permanent appearance?
What's the GEC for inside the transformer, you said you bonded in the panel?
And I don't think I see a GEC in that flex?

All good questions.......further proof I need a computer upgrade.

Sparky Joe · 09-19-2007, 02:41 AM

Quote:

Originally Posted by Celtic

All good questions.......further proof I need a computer upgrade.

I've got 2 19" wide screen LCD's side by side, and with IE7's on the fly zoom i don't miss a thing.

Celtic · 09-19-2007, 09:31 PM

Quote:

Originally Posted by Sparky Joe

I've got 2 19" wide screen LCD's side by side, and with IE7's on the fly zoom i don't miss a thing.

One for each eye

...sweet

Magnettica · 09-20-2007, 04:06 PM

Quote:

Originally Posted by Sparky Joe

So why are you running 2/0 for 200 amps? or did you correct that?
Did you space the transformer at least 6" from the wall?
Did you bolt down that pallet? Why not take it off the pallet and make a more permanent appearance?
What's the GEC for inside the transformer, you said you bonded in the panel?
And I don't think I see an EGC in that flex?

All good questions indeed. And I will address them all. Between work and school (4 days per week this semester), I have been too busy to reply to this post but I have been meaning to since Tuesday.

2/0 for 200 amps?

Yup, that's whats there and no I haven't corrected it. Table 310.16 tells me 2/0 cu is good for 175 amps in the 75º column, and unless there's an adjustable trip function on the breaker, this is insuffecient for a 200A seperately derived system. Customer does not want to pay to have it corrected since it's worked fine all this time.

Did you space the transformer at least 6" from the wall?

The NEC calls for 12" spacing of a transformer if there are combustible materials within 12" of the dedicated space.

Did you bolt down that pallet? Why not take it off the pallet and make a more permanent appearance?

Nope! Job order called for relocating the existing service, nothing about removing he pallet of permanently attaching it to the floors surface.

What's the GEC for inside the transformer, you said you bonded in the panel?

That didn't make sense to me either after I got home, posted these pics, and thought about it. Thanks for pointing that out and noticing that because I may not have picked up on that. It's since been corrected.

And I don't think I see an EGC in that flex?

There was none. I do believe years ago the flex if it was less than 6' long could be used an EGC. The code has since changed that rule and now requires a seperate ground.

Here are the updated pics from today:

Sparky Joe · 09-20-2007, 08:33 PM

Quote:

Originally Posted by Magnettica

I thought you guys would appreciate seeing the hack work the previous electrician did when he originally wired this transformer.

Interesting statement, especially because the hack job was re-done and it's still a hack job.

"customer never reported any problems" will be my new excuse for undersizing wire from now on. (240.21 (B) states the provisions of 240.4(B) shall not be allowed (and beside that 175 is a standard CB size)

The transformer documention states that the transformer needs to be bolted down. And also states it needs 6" of air flow on all sides to keep cool.

And nothing appears to be corrected in the updated pics. The only difference I can see is the bare copper EGC that ran directly to the grounding electrode(though no bond with the neutral) was replaced with an insulated EGC.

And why do the "2/0" feeds block all the lower breaker spaces in the panel? That 2/0 is tough to bend, but much easier than 3/0.

What a HACK

Celtic · 09-20-2007, 08:37 PM

Quote:

Originally Posted by Sparky Joe

Interesting statement, especially because the hack job was re-done and it's still a hack job.

What a HACK

No comment on all the tape on the grounded conductor?

Magnettica · 09-21-2007, 05:45 PM

Joe, are you calling me a hack?

Cause if you are you've got some balls.

And for someone just starting out in the trade such as yourself, you've got some really big balls.

It's either this or you have some reading comprehension problems. If somethings not on the job order well then it doesn't get touched, updated, or messed with. As you gain more experience in this trade, you will learn this, hopefully. But I think right now you think you know it all (as most youngins do), and later (rather than sooner) you will learn the hard way by touching something you weren't supposed to touch and you f^%&ed some $&*^ up! I've seen this movie before.

Sparky Joe · 09-21-2007, 08:24 PM

I didn't have to call you a hack, your statements made above called you one.

You didn't simply push a transformer against a wall(which would not be possible if installed per manufacturer specifications). You installed the damn thing whether or not it was installed previously.

So did the job ticket specify adding strands to the trimmed down conductors, or were you just being a nice guy.

And I don't have to know it all, but simply where to find it, such as the current edition of the NEC

MechanicalDVR · 09-21-2007, 08:35 PM

Not taking any sides here but, when we take a job on the work we do must pass inspection when we are done. Regardless if it is on the work order or not. Maybe the guy that sold the job missed something, we still have to do the right thing and make sure it is going to pass. We install a lot of equipment that the inspectors refer to the manufacturers instructions to finish the final.

Magnettica · 09-21-2007, 10:33 PM

Joe, how do you add strands to 2/0 copper?

You're probably one one of these so-called "electricians" who has ZERO experience in remodel type jobs. Knows nothing about old work, but can do new work with no problem. But we have yet to see any of your work. YOU are the hack, and an ass, and a moron. Now go get me my coffee and don't screw it up.

By the way, there was a pair of wires "flapping in the breeze" nearby whre I was working. It wasn't on the job order to repair it, nor was the panel that got hit by a forklift and needs to be repaired. Should I have fixed it anyhow?

Go get my coffee, fool.

Sparky Joe · 09-21-2007, 10:48 PM

Quote:

Originally Posted by Magnettica

Joe, how do you add strands to 2/0 copper

You're a real sharp one there aren't you.

I do have plenty of experience with all types of electrical work, none of which alleviate the rules of the code book.

Do you not understand that you personally are legally liable for everything you touch smart guy? The insurance company will not allow the excuse "it's worked fine like that before" stand up when it comes to their money.

And your shoddy work will never earn a pat on the back from me, so quit asking for it.

Magnettica · 09-21-2007, 11:06 PM

Wheres my coffee?

Sparky Joe · 09-22-2007, 03:44 AM

Do you like your coffee with "heavy cream"? because that's about all I'd be serving you jackass.

What post is that quote of me from? Even if it is taken way out of context, I still don't see your point.

Though I did find one of your shining points, it's actually from the thread right below this one where you also used the excuse of "customer agreed" to do shoddy work.......
"I totally agree that it doesn't look great. And I wouldn't want it done like that at my house, BUT.. whats done is done." --Magnettica