Re: [TCML] Ballast Question

[drieben@xxxxxxxxxxx (David Rieben)]

Garry,

So you do have that type of piggy, then ;^) Well,
all I can say is that I hope that your 240-480 step
up transformer is a whopper if it is to drive this
beast at even a small fraction of its potential power
processing capabilities. But no, this should not
adversely affect your ballast.

--
David Rieben

-------------- Original message -------------- 
From: "garry neeley" <bamacoiler@xxxxxxxxx> 

> It is exactly a single pig from a 3-pig, 3-phase bank. It is single phase 
> but only has 2 lv bushings. It does have a 480v primary exactly like you 
> described. 50kva. But it is the only pig I have so... No problems with the 
> ballast behaving properly? 
> 
> Garry Neeley 
> 
> On Tue, Aug 19, 2008 at 2:13 PM, David Rieben wrote: 
> 
> > Hi Garry, 
> > 
> > No, I don't see any problem with doing this but my 
> > question is why do you need the extra 240-480 step 
> > transformer in the circuit, unless the low voltage side 
> > of your pig happens to be 480 volts rated instead of 240.? 
> > 480volts plus the boost from the variac would yield on 
> > the order of 550 to 600 volts into the low voltage 
> > side of the pig and if it is only rated at 240 volts, 
> > this would severely overvolt and saturate the core 
> > of the pig. Also, if it actually is rated at 480 volts 
> > across its low voltage side, you could just use the 
> > center tap of the three low voltage bushings for a 
> > 240 volt rated input tap. It does have 3 LV bushings, 
> > doesn't it? I have seen 2 LV bushings on pigs that 
> > are designed to be a single pig in a 3-pig, 3-phase 
> > bank to provide a phase of 277/480Y, 3-phase 
> > service, but these are generally larger transformers 
> > (25 kVA or greater rated units). 
> > 
> > -- 
> > David Rieben 
> > 
> > -------------- Original message -------------- 
> > From: "garry neeley" 
> > 
> > > Hey guys I just have a quick question here. In my setup I'm gonna take 
> > 240 
> > > from the wall to a -280 v out variac to a-240 to 480 step up xformer to 
> > the 
> > > -ballast to the -pig. Do you guys think there will be any problems with 
> > > this because I have the extra step up transformer in the circuit? Any 
> > > thoughts, ideas? 
> > > Bamacoiler 
> > > _______________________________________________ 
> > > Tesla mailing list 
> > > Tesla@xxxxxxxxxxxxxx 
> > > http://www.pupman.com/mailman/listinfo/tesla 
> > _______________________________________________ 
> > Tesla mailing list 
> > Tesla@xxxxxxxxxxxxxx 
> > http://www.pupman.com/mailman/listinfo/tesla 
> > 
> _______________________________________________ 
> Tesla mailing list 
> Tesla@xxxxxxxxxxxxxx 
> http://www.pupman.com/mailman/listinfo/tesla 
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla