Doctor Drivel wrote:
"Dave Plowman (News)" wrote in message
...
In article ws.net,
Doctor Drivel wrote:
When was it universally adopted?

They came in after WW2

You don't say..

Oh - I do.

That's good enough for us then. Did they wire up the WW2 battleships
with square 3-pin plugs?

Dunno but I found this interesting...

(from http://www.lsionline.co.uk/lsi/features/articles/sep2004_2.asp)

"Shipboard electrical systems are unusual in that supplies are normally
delta wired, so there is no neutral. The ship's hull is used as earth, but
leakage currents to earth are not allowed as it causes corrosion of the
hull. It can also be an electrically noisy environment, which can cause
problems if the correct precautions are not taken. Supply voltages for stage
equipment vary with 220V, 400V and 440V all being used on different ships."