BillR wrote:
My neighbour had a tradesman come round to fit some doors. He had a hand
planer and a vacuum cleaner. The planer plugged into a socket on the vacuum
. When he switched the planer on the vacuum came on also - when the planer
was switched off the vacuum ran for 10 secs and switched itself off.

This sound like a good idea to adapt to my dust extractor and lathe. I can't
figure out how to do it and don't know what the device was called, so that I
can 'google' it.

Does anyone have a circuit diagram or know how such a device works?

Before anyone suggests putting my vac and lathe on the same switch, which is
the obvious solution, my lathe is blessed with a NVR switch (i.e. if the
volts to the lathe disappear - the switch goes to the OFF position.)

http://www.axminster.co.uk/product.a...21176&recno=31

This is clearly designed for the UK/Irish market, but I'm guessing it's
probably available in a form suitable for left-pondian electricity too
somewhere.

--
Alun Saunders