On Sat, 19 Apr 2003 21:12:57 +0100, Dave Liquorice wrote:

On Sat, 19 Apr 2003 19:09:35 +0100, Warwick Dumas wrote:

Red = HV* electricity

* LV 250V, 250 MV 500, HV 500V

Bloody hell.

Er, why? 11kV under ground is *very* common. I think there are parts
of the supergrid under ground as well, 250kV. If not some of the 125kV
stuff will be, probably oil encased and the oil circulated to provide
cooling.

Possibly Dave, Warick is questioning your definition of the voltages - as
I also did. The ususal bands are (IIRC!):

LV is usually defined as 200 - 600V (1 phase) or 400 - 1000V (3 phase).
MV is 1kV - 11kV - 33kV(3phase)
HV is 33kV and higher (up to 400kV in this country)

There is also ELV and SELV - definitions of which you should look up in
BS7676 (The IEE Wiring Regs) - these are extra low voltages.

Sarah