On Jun 9, 1:34 pm, "Member, Takoma Park Volunteer Fire Department"
wrote:
bejay wrote:
On Jun 8, 8:34 am, terry wrote:
PS. In other words you can't just depend on throwing the main circuit
breaker 'off' then having hooked it 'start up the generator'.

It would work but not safe.

What you need ( and I think is required) is an automatic transfer
switch. When the loss of utility power is detected, the switch will
automatically disconnect the utility power and switch over to the
generator. The switch usually requires a control module for detecting
the change in voltage. Companies such as ASCO build switche modules.
They ain't cheap and with good reason. It has to be fool proof for
many of the reasons stated.

Were do you guys get the idea that the transfer interlock has to be
automatic and external to the circuit breaker panel. There are transfer
interlocks available from at least two manufacturers that are manually
operated and are installed inside the panel's enclosing cabinet. The
include a manual means that prevents the simultaneous closing of both
the main and the generator circuit breakers.
--
Tom Horne
..
Can't recall anyone saying it had to be 'automatic'! Just that there
should be an interlock.
Some who posted feel that the interlock would be some sort of device
'between' the meter of the incoming utility electric supply and the
fuse panel.
There may be other ways of doing it within the circuit panel, as
mentioned by Tom Horne.
Some 40+ years ago I had a Pushmatic Panel that would have been ideal.
It had two breakers in the input section . If those two could have
been interlocked mechanically in some manner so that manually they
could not both be 'on line' at same time it would have been safe.
The OP keeps asking 'What is needed'? Considering the manner of asking
hope that someone competent is hired to do the actual work!