6 Feb
2011
6 Feb
'11
1:14 p.m.
On 2011 Feb 6, at 12:23 PM, Tony Duell wrote:
I think we are ageed on the following (and there are plenty of books to
back this up ) :
US 23)V mains is 115-0-115V with the centre tap connected to something
close to local ground. Therefore the peak votlage between any
current-carrying conductor and ground is 115*qrt(2)V
UK 230V minas has one side connected to something close to local
ground.
Therefore the peak voltge between a current-carrying conductor and
ground
is 230*sqrt(2)V.
This may make a difference in some cases, but _I_ feel that the number
of
cases where that matters is vanishingly small.
But also US 230V mains has that centre-tap available, so you can wire
part of your device to run from 115V (centre-tap to one outside wire)
if
you want to. I understnad this is commonly done to power control units,
lamps, timers, etc.
UK mains does not hve an avialable centre tap. if you want 10V you have
to use a step-down (auto)transformer.
Practically, if you want to run a US 230V device in the UK, it is much
more likely you will have to provide 110V as well than that you'll ahve
to worry about something breaking down due to the higher peak voltage
to
ground.
Yes, all of which was covered earlier in the thread.