RE: Enough pork in this pig???

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Loudner, Godfrey by way of Terry Fritz <twftesla-at-qwest-dot-net>" <gloudner-at-SINTE.EDU>

Hello Bart

Well I also might be missing something. But I'll detail my reasoning. It
would be expensive make a small three phase 7.5 kVA pole pig, thereby the
pig must be single phase. Upon seeing that 12,470 = 7200xsqrt(3) and the
plate written 120/240, I concluded that 240 volts in the two outer low
voltage terminals would make the pig deliver 7,200 volts. The 12,470 volts
must be for a wye connection between three pole pigs. The 12,470 volts must
also be the line voltage between phases from a three phase generator  with
7,200 volts between anyone of the phases to neutral. But John wrote that
most pole pigs would saturate at 1.2 of the plate voltage. So the pig will
probably saturate at 288 volts and my suggestion that the pig might not
saturate at 415 volts is invalid.

Below 7.5kVA / 7200V = 1.0417A. It seems like you are thinking that 120
volts into the two outer low voltage terminals will give 7,200 volts output.

Godfrey Loudner   

      

> -----Original Message-----
> From:	Tesla list [SMTP:tesla-at-pupman-dot-com]
> Sent:	Sunday, April 28, 2002 4:35 PM
> To:	tesla-at-pupman-dot-com
> Subject:	Re: Enough pork in this pig???
> 
> Original poster: "Barton B. Anderson by way of Terry Fritz
> <twftesla-at-qwest-dot-net>" <tesla123-at-pacbell-dot-net>
> 
> Godfrey,
> 
> I'm confused. I understand a 12470Y is (12470/sqrt(3)) = 7200V single
> phase
> (as the plate rating
> identifies). At the rated 7.5kva / 7200v = 1.0417mA. With 240v applied,
> you
> get 14.4kv at 30kva.
> Granted, that might be pushing it a wee bit much and 170v input is a
> better  
> figure as it will double it
> to 15kva. But how do you figure applying 415V? I don't think it can take
> that much. Maybe I've missed
> something here (wouldn't be the first time).
> 
> Bart
>