Ah BTW, here all the power distribution up to 20 kV is below the ground,
i.e. in cables, since the 60's. Some over-land wires are still existing
in the country-side though. In Berlin, they even use short (some km)
400kV cables to bring the electricity in the center of the city. In the
cities you don't find any cables at all above ground.
73, Stefan
Am 10.10.2011 21:42, schrieb Stefan Schäfer:
In Germany we all have a 3 phase 400 VAC system in our houses. Usually
the kitchen oven and/or continuous flow water heaters are connected to
a 3 phase system (the water heater is rated at 3x35 A, i.e. 20 kW).
There is a 120 deg phase shift between the hot wires (black, black,
brown), a neutral (blue) and protection earth (green-yellow). So in a
symmetric 3 phase load (like a motor or the water heater) the current
in the neutral conductor becomes 0. A usual power socket is rated at
16A, i.e. a single phase radio amateurs home PA can have up to 3.5 kW :-)
If a 3 phase system is rectified for a PA, there is no voltage-0, so
smaller caps can be choosen. Also the times between the amplitudes are
reduces to 20ms/6=3.333 ms.
Voltage levels are 230/400V, 20kV, 110kV, 220kV and 400kV. Some old
systems at 10kV and 30kV or 6kV for industial motors are still
existing...
Rated current of a 400kV system is 3.15 kA.
OT but Interesting differences in the countries.
73, Stefan/DK7FC
Am 10.10.2011 18:35, schrieb mal hamilton:
Hi Bob
The normal mains supply to houses and offices is 230 volts ac at 60
amps. 50
Hz. For large industrial machines in factories they would normally
have a 3
phase 440volt AC/50 Hz supply.
Some private properties do have a 3 phase supply if required for small
garage industries or hobbies like lathes etc
The normal houshold 230v appliance cord/lead is BROWN LIVE, BLUE
NEUTRAL and
GREEN/YELLOW EARTH.
Some appliances like hoover carpet cleaners, plastic encased have 2
wires ie
BROWN LIVE, BLUE NEUTRAL and no earth.
The plug to the mains socket is clearly marked when you make a cord/lead
connection so the wires do not get crossed over and the plug is non
reversible.
The 3 pin plug contains a fuse always in/to the live pin.
It is a straight forward safe procedure avoiding crossed Live and
Neutral
wires.
In EU the supply is normally 220 v but might vary in different
countries.
De mal/g3kev
----- Original Message -----
From:<[email protected]>
To:<[email protected]>
Sent: Monday, October 10, 2011 3:15 PM
Subject: Re: LF: mains wires
in the US we have a standard of 120/240
with the 120 as the appliance voltage
the British and others use 220 for a standard
does that mean that 440 is used for the big power draws
we would place our clothes dryers on 220 do you have 440
in general use in the home
Bob K3DJC
On Sun, 09 Oct 2011 22:44:20 -0400 Elton A
Sanders<[email protected]>
writes:
If it was plugged into US 230v both Black and White would be hot.
Mains
feed here is 2 hots and Neutral hot to Neutral 115v hot to hot 230v
(feed is from a center tapped transformer on the pole).
WB5MMB
On Mon, 10 Oct 2011 01:25:02 -0000, mal hamilton wrote:
Bob
If you look at a Dentron 2500 amplifier on the cct diagram the
230v
mains cable, WHITE wire goes to the ON/OFF switch on amplifier
then
primary of HT transformer which to me is HOT and BLACK wire goes
directly to the other side of primary winding, NEUTRAL and GREEN
to
chassis.
In the UK the switch is always in the LIVE (hot) wire and NEUTRAL
direct to the appliance except it happens to be a double switch.
UK appliance BROWN live, BLUE neutral, plus an earth wire (3 wire
appliance)
mal/g3kev
----- Original Message -----
Sunday, October 09, 2011 7:48 PM
Re: LF: mains wires
what I use to keep track
Black is hot white is not
Bob K3DJC
On Sun, 9 Oct 2011 17:09:09 -0000 "mal hamilton" writes:
LF
I have a USA amplifier with 230v input. The mains wires are
BLACK, WHITE, and GREEN
The cct diagram shows White as the live wire with amplifier
mains
switch in this line, Black goes to the other end directly to
transformer primary
and Green to earth.
but
according to USA info the Black wire should be Live and White
Neutral.
So beware !!!!!!!!!!!!!!
de g3kev
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