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#163767 05/16/07 04:24 PM
Joined: Oct 2000
Posts: 3,666
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Quote
All,

I have viewed your website a lot of times and watched in amazement at some of what is posted. I'd rather watch, however, a transformer started making some funnny noise when I was on site, and I de-energized it without permission. Attached are some of the photos, pay close attention to phase A.

Dennis W.
Minneapolis

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Joined: Feb 2002
Posts: 840
C
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There could be a slight problem with that. wink


Peter
Joined: Feb 2003
Posts: 939
F
Member
Ahh good catch there.

i am suprised that it did not trip the OCPD yet shocked

Merci, Marc


Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

Joined: Dec 2005
Posts: 866
Likes: 4
R
Member
Good call to shut it down.

Looks like a loose connection in that jumper, overheated and arced away the flat tab of the lug and terminal of the TX.

Cheers

Raymond


The product of rotation, excitation and flux produces electricty.
Joined: Oct 2004
Posts: 806
Member
Dennis W:

A question: Can you describe the "funny noise"? I have a theatre with a similar Tx that makes a peculiar high-pitched buzz/whine..didn't notice any burning smells but it sure is loud!

Joined: Feb 2003
Posts: 288
Y
Member
Good call. I'd say that transformer would be pretty noisy anyway, what with the hard-piped connections. I'd guess the funny noise would be something other than 60Hz plus harmonics, no?

Joined: Apr 2002
Posts: 7,283
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For a 300KVA xfr, the secondary conductors seem a little on the wimpy side??

300KVA is usually 800 amp secondary MOCP @ 208 volt, 3 phase.

Oversized xfr?? Not that it matters now, but I'm curious.
John


John
Joined: May 2003
Posts: 2,876
E
e57 Offline
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Ah, I have seen this before - the "Melti-tap" transformer.

When I was younger and far stupider than I am today. I did a service call for mixed voltages at a supermarket, and went all over trying to find the place that had a neutral - all the way back to the transformer and pulled the cover off (LIVE - DUMB) to find a glimering molten pool of Aluminum. Do ya know that feeling like you're looking at a nest of angry hornets close up? "I'll just put this cover back on with 2 screws, and get away from this fast..."


Mark Heller
"Well - I oughta....." -Jackie Gleason

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