In article ,
"Dave Plowman (News)" writes:
In article ,
S Viemeister wrote:
Input 120v 60hz 15 or 20 amp 3-wire only

Well, that doesn't tell you its power consumption - only that it's less
than 1800 watts and it needs to be earthed.

Output 650 watts 2450mhz 11 amp

That seems even worse. 650 watts at 120 volts is 5.4 amps.

It's an old unit, the label says it was manufactured in January 1989.

Yes, so efficiency of about 50%, which is typical then.
Power factor of microwave ovens is not quite 1, but it's
near enough that can probably be ignored at this level.

I don't remember the rating of the one we have in Scotland, but it cooks
faster than this one.

Domestic UK ones are typically 600 to 1000W output, so your
UK one could well be more powerful.

--
Andrew Gabriel