In Denmark for larger appliances and stove tops we have five wires; three
live, one null = neutral, and earth. For such appliances, the law says that
you have to use a qualified electrician. However just recently with a new
induction stove top, the electrician made a mistake in selecting the null
wire at (in) the fuse box, so I had to fix it myself. The stove top
required connections to two live wires, the null wire, AND the earth wire.
The old top, installed many years ago, did not use null. The total voltage
used with the two live and null was about 230v (nominal 220v).
Before I fixed the electician's error at the fuse box, I could measure
around 190v between the null wire and the two live wires, even though that
null wire actually connected to nothing at the fuse box end. The stove top
would not work though, presumably through lac k of current (any comments?).
I ought to have taken an OM photo of the bad installation!
Roger Key
Foxy wrote:
Again I'm a little late on this one.
Why have an active and a neutral? The neutral is bonded to earth. The AC
flows forward and backward at 50/60 Hz. So for the first 10 milliseconds
the
voltage rises to 240 volts (actually 339, but let's not go there) above
earth, then in the next 10 milliseconds it goes 240 volts below earth. It
doesn't matter what direction it is - above or below earth - it still
hurts.
Foxy
----- Original Message -----
This has just reminded me of a question that's been bugging me since
school physics class. If we run alternating current on the power
supply, with the current reversing 50 or 60 times a second, why bother
labelling live and neutral and having to remember which way round to
stick the wires in the plug. You get it wrong and 1/50th of a second
later you got it right. What's the difference between live and neutral?
The olympus mailinglist olympus@xxxxxxxxxx
To unsubscribe: mailto:olympus-request@xxxxxxxxxx?subject=unsubscribe
To contact the list admins: mailto:olympusadmin@xxxxxxxxxx?subject="Olympus
List Problem"
|