On Wed, 16 Apr 2014 15:29:18 +0100, Tim Watts wrote:

On 16/04/14 16:02, Tim Streater wrote:
In article , Uncle Peter wrote:

I read somewhere that 60Hz is actually the most efficient for
transformers
and motors, and we are wasting 20% of our power over here using 50Hz.

Wasting it where? You imagining that every time juice is shoved through
a transformer anywhere in the UK that we waste 20% ??

If that was the case then (a) there's be **** all by the time it
arrived at your house and (b) all the transformers would ****ing melt.
Do you know how much power goes through a transformer? And you're
suggesting that 20% of it gets turned to heat there?


Exactly. Losses more like 1% or less for medium sized transformers...
That's still warm at 500-1000kVA

I've got a 12V AC transformer here (wall wart) that gets very warm with no load! Weird thing is it's the same temperature with full load?!?

--
If one of the questions in a GCSE exam was "express 4.8% as a fraction", 4.8% would give "low battery".