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This "Accident" happened at a datacenter in Florida. They had 2 on-site
255kw gensets for emergency backup, and one of them had a defective bypass
contactor from salty air corroding the contacts. For testing, an
"electrician" had bypassed the contactor "temporarily" to test the setup.
Supposedly, While he was off getting parts, the grid went out and the
gensets both started and one of them backfed the grid. The power was out
because of a wind-downed line on 14.4kv feeder down the block. When Florida
power arrived on-scene they found a wire down, with both ends hot, and all
power working normally in the area! Imagine their suprise!

The genset was backfeeding 240v 3-phase into a pad-mounted 14.4kv
transformer, causing it to make the segment hot again. They figured out
what was going on before anyone got killed, and pulled the underground
feeder with a hotstick. They did not bother to reconnect the datacenter's
power, and they lost power after 4 days and took out a segment of the
internet.

The datacenter had to get fuel delivered, as it was 2 more weeks before the
power company would re-connect their power. An electrical contractor had to
be called in to re-certify the whole system and then the local electrical
inspector had to sign off on it. Only then did they get their power back.
The "electrician" was fired.

If there had been people near that downed 14.4kv wire, now made hot again by
the gensets, someone could have easily had been killed. Imagine if you were
that electrician and due to your mistake you had killed a small child.

-Phil
----- Original Message -----
From: "David Roden" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Friday, October 12, 2007 3:25 AM
Subject: Re: [EVDL] Vehicle to Ground, comments


> This thread is almost off topic, but recall that the initial impetus for
> it
> was a discussion of using an EV battery for standby or backup power for
> one's home.
>
> On 11 Oct 2007 at 2:43, Bob Rice wrote:
>
>> >
>> > 1. It requires a cable with two male connectors, which could
>> > electrocute a
>> > careless user or child.
>>
>> > So you use Anderson connectors. They won't be "hot" like a double male
>> > 'stench cord.
>
> That's a different situation. Now you have connectors being installed
> contrary to their manufacturer's instructions. They're also being used
> for
> a non-approved application. It may be safer, but it's still a code
> violation.
>
>>
>> > 2. Without a proper transfer switch, it could accidentally backfeed the
>> > grid and KILL a lineman who is expecting the line to be dead.
>> >
>> But IF you Isolate yourself with the House breaker OFF it can't
>> backfeed!!
>
> Accidents happen.
>
> 1. You're watching the big game with the gang and drinking lots of beer.
> The power goes out and you puff out your chest and say, "I can fix this."
> You stagger out to the garage with your whole retinue in tow, everyone
> doing
> lots of alcohol-fueled joking and chattering. You fire up the genset and
> plug it in. The lights come on! A beery cheer rises from the assembled
> multitude! Back to the TV!
>
> Oops, you were so busy showing off that you forgot to open the main
> breaker.
> You won't notice until the power comes back on. You probably won't even
> know about the lineman who fell, and is now a quadraplegic, because he was
> shocked by an unexpectedly hot line.
>
> 2. You're working late at the office. Your spouse calls - "The power went
> off, and the freezer is starting to thaw." You're in a hurry to get done
> so
> you rush through describing how to hook up the EV to the house. You never
> realize you forgot to tell your spouse to open the main breaker.
>
> These are only two scenarios. If it is possible to backfeed the house and
> leave the main breaker on, it WILL happen someday.
>
> For around $100 (I found one on Ebay for less than $50) you can make that
> impossible. That will buy a simple 60 amp Square D panel with two
> interlocked breakers, one for the feeder from the main panel, one for the
> feeder from your EV inverter (or a genset). They have a mechanical device
> that makes it impossible for both breakers to be on at once. Mine can
> feed
> eight 120v circuits and they are available in larger sizes. These are
> relatively inexpensive, simple, straightforward, approved transfer
> devices.
> Get one. Use it.
>
>
>> > 3. If you should power your house this way and forget to open the main,
>> > when the power came back on, your genset could explode, killing or
>> > injuring
>> > you or a family member, and setting your house on fire.
>>
>> But in reality you WOULDN'T be backfeeding into the line. You
>> isolated
>> the house BEFORE starting up the genny.
>
> Only if you're using a transfer switch or panel as described above.
>
>> The genny would trip out(good thing!) IF you were careless enough to
>> TRY to backfeed.
>
> Perhaps. It isn't foolproof. The result I described HAS happened to
> people.
>
>> Pull the meter out of the socket,
>> if you KNOW the power will be out,for awile, like days!! Then , when the
>> chrisis is over you 'fess up to the 'lectric Co. they'll reseal it.
>
> a. Same problem as above - you have to remember to do it.
>
> b. Many power companies will be VERY upset if a homeowner breaks the seal
> on the meter. This may have worked for you years ago, but today at least
> some of them will accuse you of tampering and stealing power. They may
> well
> shut you off.
>
>
>> > This stuff isn't for the faint hearted. You don't just sit somebody
>> > up front in a 747 that has never flown before or a guy that never drove
>> > an
>> > 18 wheeler BEFORE ya make darn sure he knows what he is doing!
>
> But that's the problem of talking about it in a public forum - all kinds
> of
> people with little or no electrical experience will read it and try it.
>
> I think of the wiring that was in my current house when I moved in. The
> former owners thought they were electricians. They had fastened NM cable
> to
> the baseboard by driving nails through it. They had run old knob and tube
> wiring through the furnace ducts with no protection; the insulation had
> mostly flaked off. Inside the walls I found wiring done with rubber
> extension cords, and splices twisted and taped and then stapled to the
> studs. It's a wonder the house was still standing. People like that
> shouldn't be allowed to plug in a toaster (only a slight exaggeration),
> much
> less connect standby power to a house.
>
>
>> > In our litigious society, it is a very bad idea to suggest this
>> > practice
>> > in a public forum.
>>
>> > Unless it is explained HOW to correctly!
>
> Ah, but you didn't do that. You explained how to do it in a very
>>hazardous< manner.
>
>> > When ya buy a genny, at Home
>> > Despot, they show ya how to hook up an Isolation switch, or give ya the
>> > number of an electrician, to set it up for you.
>
> I wouldn't trust a Home Depot (or Lowe's) employee to show me how to open
> the box it came in!
>
> And what about when you buy an inverter to use with your EV on Ebay? Does
> the seller give you instructions? Does he tell you to have an electrician
> install it? Not anyone I've dealt with!
>
> It IS possible for a DIY to install a standby power system safely. You
> can
> find instructions in books at the public library and perhaps even online.
> But posting that you power your house by backfeeding through your EV
> connection is not going to help them set their system up right.
>
> David Roden - Akron, Ohio, USA
> EVDL Administrator
>
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