Reminder: Never connect a generator to home wiring without transfer switch

Wed Aug 25 17:52:18 UTC 2021

In theory, Jay is correct, but assuming that theory will always work in
practice is, in this case, how linemen end up dead. We're all well aware of
never assuming theory = practice, but admittedly the stakes tend to be a
little lower in our world.

Ensuring that a generator physically cannot backfeed is just one layer of
protection against the already very high risk of the job of a lineman. Then
there is, of course, checking for the presence of voltage before starting
work, but it's possible for a generator to start AFTER this check.

Another layer of protection is grounding all conductors prior to beginning
work, so that if power does come back (via the grid or a backfeed) A: The
lineman and bucket is not the best path to ground and B: The source is
tripped.

Reading through that forum post, it sounds like that particular contractor
had a reputation for lacking proper safety precautions, so one or more
safety layers may have been removed, making the risk/impact of any single
mistake much greater than it should be.

-Matt

On Wed, Aug 25, 2021 at 11:25 AM Mel Beckman <mel at beckman.org> wrote:

> Jay,
>
> No, because transformers work in both directions :)
>
> Plus, to the previous commenter that talked about “suicide cords”:
> they’’re more correctly termed “homicide  cords”:
>
> “ The lineman killed yesterday was working for Pike Electric and picked up
> a line that was connected to someones house that hooked up a generator and
> did not disconnect from the distribution system. The linemans name was
> Ronnie Adams, age unknown. He had two children and a wife. As far as I know
> he was from Louisiana. They are trying to set up a fund for his family, but
> nothing I have heard of yet. I will let yall know more as I hear of it. I
> wish they would really teach folks the proper connection of generators,
> this was a really tragic and preventable accident. Stay Safe and think
> about it before you do it.”
>
> https://powerlineman.com/lforum/showthread.php?711-Storm-Death
>
>  -mel
>
> On Aug 25, 2021, at 10:12 AM, Jay Hennigan <jay at west.net> wrote:
>
> On 8/25/21 07:04, Mark Tinka wrote:
>
> On 8/25/21 15:59, Ethan O'Toole wrote:
>
>
> How would this not load the generator or inverter into oblivion?
>
> Not sure I understand your question. Say again, please.
>
>
> If you fail to isolate your generator from the incoming utility feed so
> that you're back-feeding the utility and the power is out for your
> neighborhood or the whole city, would not the load of trying to light up
> the whole town completely overwhelm your little generator to the point that
> it fails, stalls, or trips its own output breaker?
>
> --
> Jay Hennigan - jay at west.net
> Network Engineering - CCIE #7880
> 503 897-8550 - WB6RDV
>
>

-- 
Matt Erculiani
ERCUL-ARIN
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