In article , (Chris Lewis) writes:
| According to Dan Lanciani ddl@danlan.*com:
| In article ,
| (Chris Lewis) writes:
|
| | This device conceptually just makes the meter base larger, and has
| | provisions for security sealing it too. Otherwise, FPL wouldn't
| | permit it. Obviously they do.
| |
| | But I would imagine that the local power authority has to approve
| | of the device before they'd allow you to install one.
| |
| | [I believe that contractors have to contact the power
| | company to inform them that the meter base has been diddled
| | with so they can come out to reseal the meter.]
| |
| | If you were to somehow get a hold of one up here, you really should
| | call the power company before installation.
| |
| | Is UL listed the same as UL approved?
| |
| | Yes. Which means it's approved up here unless it runs afoul of
| | something specific in the CEC, or Hydro throws a fit.
| |
| | [Ontario Hydro has two separate "special" meter trial programmes going
| | on, similarly restricted in region. "Smart meters" and something
| | else I forget...]
| |
| | To tell you the truth, I'm _very_ much surprised I haven't seen
| | something like this before. It's the obvious place. It's
| | just not something a homeowner is usually able to install
| | themselves ....
|
| One concern I have is the neutral/ground connection between the base
| and meter. To the extent that it exists at all it is not intended to
| handle much current; most split-phase meters are 4-wire devices. I
| assume (hope?) that installation of the adapter involves some sort of
| jumper which in turn might require an additional lug to be added to the
| original base.
|
| You'd have to install a jumper on the neutral bar to the special
| generator plug I guess.

Right. And that of course might involve installing an extra lug or
a different bar. (The typical meter base here has either two full-
sized neutral lugs to join the incoming and outgoing feeds or that
plus a smaller terminal for a local grounding electrode conductor.)
It's too bad since it is so close to a plug-and-play solution... but
not quite.

| | An even simpler way would be to have some sort of object that "mimics"
| | the back of the meter and has a plug for the generator. Power out, yank
| | the meter, install the adapter, plugin the generator, and voila!
| |
| | When power comes back, pull out the adapter and plug the meter back
| | in.
| |
| | Problem being that you'd have to get the power company back to
| | reseal the meter after grid power is restored.
|
| [Obviously it wouldn't work as stated, because the meter plug doesn't have
| a neutral.]
|
| In addition to the neutral/ground problem, what if you accidentally
| install the adapter upside down? Around here bases are typically
| symmetrical so I'm not sure you could make the adapter failsafe
| against back-feeding without modifying the base. But then you'd
| want to arrange that the adapter couldn't be inserted into an
| unmodified base which would make the base incompatible with a
| normal meter...
|
| There's a patent on that:
|
| http://www.okpatent.us/medicinal_den...wer_meter.html

Yes, that solves the easy part. As I said, you can modify the base such
that the adapter plugs in only the right way (and still support a normal
meter or even one modified per that patent). But what you really need
is to prevent the adapter from fitting an unmodified base at all--otherwise
somebody is going to plug into the wrong base and back-feed. Once you've
gone to all that trouble and added a neutral connection you might as well
replace the entire base with one that includes a generator plug. Maybe
that should become a standard product for new construction.

| Note that if the generator doesn't bond ground and neutral, you apparently
| don't have to switch neutral.

Yes, the NEC recognizes generators connected not as separately derived
systems. None of my transfer switches switch the neutral. Interesting thing
about my transfer switches in connection with the original part of this
thread: they are not DPDT knife switches but pairs of DPST knife switches
with a mechanical interlink. I assume this is done to avoid making the boxes
extremely deep. These are UL listed Cutler-Hammer units professionally
installed and inspected.

Dan Lanciani
ddl@danlan.*com