In article , The Other Mike
scribeth thus
On Wed, 18 Apr 2012 14:19:15 +0100, tony sayer
wrote:

Next question is what sort of size are the transformers involved for
that?.


Remember that is not just one transformer, the supergrid is an
infinite bus, everywhere has at least two points of infeed.

Yes ..

The
circuit breakers are only rated at 50000A so everything else has to
follow suit.

50 K amps;!.. Impressive!, the ones you see in some Youtube vids don't
quite look that serious but I suppose must be..


But the transformers are big - 1000MVA and weighing a couple of
hundred tonnes or thereabouts.

Taking the 11 kV IIRC up to grid distribution and back down for 132
Local. Last time I saw one it didn't seem -that- big?.

Might have been mistaken tho!.

Are these a type of autotransformer or with separate primary/secondary
windings?..

In the UK everything 400/275 or 400/132 or 275/132 is an auto
transformer.


Right.. Thanks no need for isolation as such..


--
Tony Sayer