On Saturday, May 25, 2019 at 10:05:49 AM UTC-4, wrote:

The only problem with the mechanical interlock is that
you don't know when power had been restored ...
no street lights here, but I did happen to see a light in
the neighbor's house, but that's pretty far away. BTW, there are
"reverse alarms" available to detect power returned and sound an alarm.
I have not installed one of these yet.



" Power-Back "

https://www.amazon.com/Reliance-Cont.../dp/B003KREORA

I just installed one last year - no problems -
and the screeching loud noise would probably
even wake me in the night.
Keep earplugs handy to get to the panel to turn it off !
.. it's painfully loud & an awful screech.
John T.

I didn't know these existed. Looks like it uses an inductive pickup
to determine when power is present on the incoming conductors? Good
to know they exist. Lucky here, there is a street light in front of
my house, only one on the whole street. How that came to be, no idea.
But that's far from perfect, at night you have to keep checking and
it's useless during daytime.