For safety checking, one can use a Wiggy (still made),
or a neon bulb
probe.
For what its worth, those neon bulb probes are often referred to
generically as Wiggies as well.
I was chatting with one of our electrical co-op's
linemen. He
mentioned that when dealing with outages, that disconnected lines
sometimes aren't. Apparently some workers have been surprised when
some enterprising homeowner decided to fire up his portable generator
without pulling the main disconnect.
What kind of monster generator did this homeowner have?! The normal
little portables will instantly disconnect (breaker or otherwise) if
you try to connect it to a blacked out grid, with all those people in
dark houses with the lights and fridges still connected. That's one
helluva load.
--
Will