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#163767 - 05/16/07 04:24 PM 300KVA Transformer photos  
Admin  Offline

Administrator
Member
Joined: Oct 2000
Posts: 3,443
NY, USA
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

[Linked Image]

[Linked Image]

[Linked Image]

[Linked Image]

[Linked Image]


Tools for Electricians:

#163768 - 05/16/07 05:41 PM Re: 300KVA Transformer photos [Re: Admin]  
CTwireman  Offline
Member
Joined: Feb 2002
Posts: 840
Connecticut, USA
There could be a slight problem with that. wink


Peter

#163780 - 05/16/07 09:04 PM Re: 300KVA Transformer photos [Re: CTwireman]  
frenchelectrican  Offline
Member
Joined: Feb 2003
Posts: 939
Wi/ Paris France { France for ...
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?)


#163790 - 05/17/07 07:49 AM Re: 300KVA Transformer photos [Re: frenchelectrican]  
RODALCO  Offline
Member
Joined: Dec 2005
Posts: 854
Titirangi, Akld, New Zealand
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.

#164109 - 05/25/07 01:48 AM Re: 300KVA Transformer photos [Re: RODALCO]  
mxslick  Offline
Member
Joined: Oct 2004
Posts: 803
Atomic City, ID USA
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!


#164494 - 06/04/07 06:56 PM Re: 300KVA Transformer photos [Re: mxslick]  
yaktx  Offline
Member
Joined: Feb 2003
Posts: 288
Austin, Texas, USA
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?


#164503 - 06/04/07 07:47 PM Re: 300KVA Transformer photos [Re: yaktx]  
HotLine1  Offline


Member
Joined: Apr 2002
Posts: 6,824
Brick, NJ USA
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

#164553 - 06/06/07 03:36 AM Re: 300KVA Transformer photos [Re: HotLine1]  
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
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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