Re: Pole Pig position

Tesla List wrote:
> >From steve.date-at-telops.gte-dot-comWed Aug 14 22:09:55 1996
> Date: Wed, 14 Aug 96 10:01:13 -0500
> From: Steve Date <steve.date-at-telops.gte-dot-com>
> To: tesla-at-poodle.pupman-dot-com
> Cc: Steve Date <steve.date-at-telops.gte-dot-com>
> Subject: Pole Pig position
> Hi all,
> I am getting to the design of the "structure" of my system and I have
> decided to mount the whole system on two "pallet" type boxes with the
> control panel and pig in one "box" and the caps,rotary,etc in a second
> (with the coil mounted on top) and the two pallets connected with 30 feet
> of cable.  This config would allow me an easy way to haul it around in my
> pickup.
> Anyway....................
> Seems like a "normal" layout, but my question is this:  Can I mount the
> pole pig laying on its side?  I have a 5KVA pig and I know it's filled
> with oil, however I can hear that it is not full (expansion room with
> air?).  If the oil is there for cooling and moisture exclusion I would
> think it maybe OK to lay it on it's side, but if its main function is for
> insulation, having the windings stick out of the oil might not be the way
> to go.  Laying the pig on it's side would make for a much better layout.
> Any comments regarding the basic layout and/or position of the xformer
> would be appreciated.
> Steve Date  GTE-NW
> INS Regional Support - Voice Services
> M/S WA0103FS
> 1800 41st, Everett WA   98201
> (206) 261-5303 voice
> (206) 261-5979 fax


I would advise against the sleeping pig version of transformer mounting.
It really has nothing to do with heat disappation. (You will never get 
the thing warm in Tesla service)  The #1 reason is that it was never 
designed to be installed that way.  A lot of good engineers have worked 
hard to design it for vertical, upright mount only!!  The problem is with 
leakage.  The seals in a pig are of course quite good, but over time the 
oils used have a way of finding an out.

Insulation wise, you will definitely uncover the high voltage portions of 
the transformer too!!  The avearge pig is never filled even 3/4 full!!  
Only the highest voltage transformers are filled to the bushings.  The 
hot leads are always heavily insulated and don't require oil covering. 
besides, the HV insulators traditionally extend deep into the can to the 
oil level anyway.  I have seen a lot of different designs.  The main 
thing is to not uncover the core of the transformer.  This will happen on 
its side!!  You would have to be absolutely certain the pig was filled 
almost to the brim!  A dangerous thing to do.

I would pull the core if space is a problem and custom make a smaller 
rectangular tank for the core and oil.  Remember, heat is not a problem 
at all. only proper insulation and oil leakage.

Richard Hull, TCBOR