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#183394 - 01/08/09 02:34 AM Old Power Company Transformer  
Admin  Online Content

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Joined: Oct 2000
Posts: 3,439
NY, USA
Quote
Spotted this one when I was at a local fast food restaurant. Iím not sure how old the transformer is but Iím sure itís before my time, because Iíve never seen one like this before.

Tristan S.

[Linked Image]



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#183506 - 01/11/09 11:11 PM Re: Old Power Company Transformer [Re: Admin]  
Trumpy  Offline


Member
Joined: Jul 2002
Posts: 8,211
SI,New Zealand
I don't see any ground point on the body of the transformer.

That pole looks like it's been there a while, I see it is starting to split down the side.


Let's face it, these days if you're not young, you're old - Red Green grin

#183514 - 01/12/09 02:07 AM Re: Old Power Company Transformer [Re: Trumpy]  
Lostazhell  Offline
Member
Joined: Feb 2004
Posts: 1,429
Bakersfield, CA (Originally Or...
I've seen similar looking transformers in old parts of Santa Ana and Los Angeles in neighborhoods dating back to 1900 - 1920's


#183536 - 01/13/09 05:05 AM Re: Old Power Company Transformer [Re: Trumpy]  
noderaser  Offline
Member
Joined: Mar 2007
Posts: 404
Portland, Oregon, United State...
Originally Posted by Trumpy
I don't see any ground point on the body of the transformer.


From what I can see, it might be the bushing on the right side.


#183560 - 01/14/09 05:13 PM Re: Old Power Company Transformer [Re: noderaser]  
mamills  Offline
Member
Joined: Nov 2001
Posts: 745
Wharton, Texas, USA
I have seen a fair number of these old guys over the years. I have alway had a question about them, which perhaps someone might be able to answer. I have seen some of these pots with long leads extending from the insulators on the HV and LV sides, and I have also seen very short leads (usually from the LV side only), with splices made to additional conductors. Question; were these transformers manufactured with long leads permanently connected to the internal windings and then brought out through the insulators, or were there connector terminals inside where conductors could be attached and brought out?

In any event, those porcelain brown or white insulators are a treasure.

Mike (mamills)


#183562 - 01/14/09 06:49 PM Re: Old Power Company Transformer [Re: mamills]  
junkcollector  Offline
Member
Joined: Apr 2007
Posts: 36
Central MN
Originally Posted by mamills
Question; were these transformers manufactured with long leads permanently connected to the internal windings and then brought out through the insulators, or were there connector terminals inside where conductors could be attached and brought out?


Hi,

I've seen some pictures and drawings in old electrical books of transformer connections of these old units. From what I can tell, These old transformers had terminal blocks inside where taps could be reconnected / relinked for different primary voltages and one was able to connect the secondary for either series or parallel or series with a tap for the neutral for supplying a 120/240 volt service. Leads were already preattached to the terminals, as portrayed in an old advertisement for GE I seen once. I would assume that these connections would have been modified (If needed)either at the factory, or at the POCO's shop, and not on the job. Even in modern times this fact can probably account for the short leads that you (and I) have seen. I have seen them mainly when you can tell that there had been some work done on the secondary, such as being upgraded to triplex or such. It would obviously be much easier to splice and not open up the pot.

Regarding the picture, I don't see any primary cutout. That seems odd, because the transformer does not appear to be self protected. I'm just guessing, but just based on the size of the primary bushings and insulator on the pole, I'd say this transformer is on a 7,200 V line. (Probably rated 6,600 V)Almost all of these old transformers I seen were connected to 2400 V lines (either 4160Y/2400 or 2400 delta)

Last edited by junkcollector; 01/14/09 06:50 PM.

#183894 - 01/25/09 08:11 PM Re: Old Power Company Transformer [Re: junkcollector]  
Albert  Offline
Member
Joined: Aug 2006
Posts: 76
Falls Church, VA
Yes, the old distribution transformers had pigtail leads that were continuous from inside the "can" to the outside. They passed through hollow porcelain bushings, and the space between the bushing and the conductor was sealed with something called "compound" (a mysterious substance which had myriad uses in 20th-century electrical practice).

I believe the overhanging top of the can (a "signature" of Westinghouse transformers, though other brands may have had it as well) was intended to shield the bushings from rain.

Last edited by Albert; 01/25/09 08:14 PM.

#184314 - 02/06/09 10:56 PM Re: Old Power Company Transformer [Re: Albert]  
kale  Offline
Member
Joined: Nov 2002
Posts: 174
PCB's?


#184316 - 02/06/09 11:32 PM Re: Old Power Company Transformer [Re: kale]  
HotLine1  Offline


Member
Joined: Apr 2002
Posts: 6,809
Brick, NJ USA
Kale:

Are you wondering if it has PCB issues? Or, asking about PCB's??

The POCO xfrs here (NJ) were tagged 'NO-PCB's' for 'clean' ones; and all the non-clean ones were swapped out.

The oil within many if not most OLD transformers contained
PCB's (Polyclorinated bi-phenyls). That is a controlled hazardous item, which has caused large amount of pollution/contamination.

It was used a lot in xfr oil, and OLD magnetic ballasts. The 'newer" mag ballasts were marked "no PCB's" or "Non-PCB"

Large xfrs were 'treated/flushed' and refilled with non-PCB oil. This process did not totally eliminate the PCB contamination, it lowered the 'count' to levels acceptable to the US EPA/DEP standards.

'Old' ballasts that contained PCB's were treated as regulated hazardous waste, and required packaging into a steel drum, sealable lid, and a LOT of EPA/DEP documentation. Needless to say, this was and still is a expensive proposition to dispose of legally.

I had (customer owned) 9 'mat' setup 500Kva xfrs 'cleaned', and 3-750Kva that had to be 'disposed'. The 3x750 Kva removal/documentation/disposal by a Lic Haz Waste Disposal company was in excess of $15k, back in '81.



John

#184319 - 02/07/09 12:26 AM Re: Old Power Company Transformer [Re: HotLine1]  
junkcollector  Offline
Member
Joined: Apr 2007
Posts: 36
Central MN
Just curious John, do you know what the hazardous waste disposal companies do to get rid of PCB contaminated stuff? What do they do with the old PCB oil?


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