[Amps] Benefits of 3-phase power?

[Roger Parsons]

I too was very surprised to find HV single phase power
distribution when I arrived here from England. I had
always understood that long(ish) transmission lines
needed to be 3 phase to keep the neutral potential
close to ground potential - as there is no current in
the neutral in a balanced three phase supply. However,
the power line to this area is single phase 7.2kV and
at least 20km long. And it appears to work quite fine!

I don't see any particular advantage in a three phase
feed actually into a residence except for extreme QRO,
and possibly electric heating. Industry is a different
matter as much machinery requires significant power,
and efficiency and regulation are better with 3 phase.

I feel that history, and decisions made 100 years ago,
have much to do with power distribution systems - I
would be surprised if 120V would be the standard here
if one could start with a clean slate. And I would be
surprised if 50Hz would be the standard in Europe
under the same conditions.

One thing I found I could not live with was a 120V
electric kettle. I don't like to wait 20 minutes for a
cup of tea and was therefore forced to wire a 240V
outlet and (probably illegally) import a 240V 3.1kW
ceramic element kettle from England..... This is
possibly why North Americans drink mostly coffee.....

73 Roger
VE3ZI/G3RBP



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