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Discussion Starter #1
Re: [EVDL] Vehicle to Ground, comments

----- Original Message -----
From: "Bill Dennis" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Wednesday, October 10, 2007 10:27 AM
Subject: [EVDL] Vehicle to Ground


> We have frequent power outages at our house, so a few years ago, I wired
> up for receptacles that were totally separate from the house's main
> wiring system. During a power outage, I'd feed power from a portable
> generator into these receptacles with a generator, to keep the house's
> heating system, refrigerator, TV and a few lights working

Hi Bill an' All;

I do this all the time, too, well doing those mystery power outrages
that the Power Co is usually clueless, til you CALL them. Ha Ha they don't
seem to notice less load when I'm not tuned in?The setup I use is a 3.5kw
jenny backfeeding into my outdoor charge plug for the car/cars?Of course you
have to open the house's main breaker!!! You arent gunna light ALL of CT,
small as it is, with a Briggs and Stratten genny! Power co wiklll be pissed,
IF you could because lines that are"Dead" aren't, when they work on them.

I guees since the genny isn't grounded, per say, but it WOULD be
isolated, though? Feeding back through my 240 range plug, from it's 240
output, it seems to work OK the water pump works, the fridge churns along, E
water heater I turn off. I guess you COULD use one burner on the E
stove?Gently.Biggie is the fridge and lights. Nice to be able to use the
sink, flush the crapper, too!Since I'm back feeding through the electrical
box, THAT is grounded? I just treat the whole thing as I do my Non Isolated
charger, a PFC -20, with care and respect. I noticed at the RR setup, where
they have trailers as "Perminent" buildings they wire them throgh a BIG ass
transformer,on a pad, outside, 120/240 volts, just before the main breakers
for the trailers. Isolation for the metal trailers, safety thing I guess? My
genny is just on the ground. Insulated, of sorts, if it isn't raining?I'm
SURE it violated some code?

Seeya

Bob

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Discussion Starter #2
Re: [EVDL] Vehicle to Ground, comments

On 10 Oct 2007 at 12:05, Bob Rice wrote:

> The setup I use is a 3.5kw
> jenny backfeeding into my outdoor charge plug for the car/cars

I seldom "yell" but this is one time I think it's warranted.

WARNING. THIS IS A VERY HAZARDOUS PRACTICE.

It is dangerous and illegal for several reasons.

1. It requires a cable with two male connectors, which could electrocute a
careless user or child.

2. Without a proper transfer switch, it could accidentally backfeed the grid
and KILL a lineman who is expecting the line to be dead.

Not just make them "p**sed," KILL THEM. As in electrocution. Do I need to
make that any clearer?

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 your
or a family member, and setting your house on fire.

Let me repeat this. It is really important.

BACKFEEDING YOUR HOUSE WITHOUT A PROPER LISTED TRANSFER SWITCH CAN KILL
PEOPLE. In fact, it HAS.

DO NOT DO THIS.

In our litigious society, it is a very bad idea to suggest this practice in
a public forum.

David Roden - Akron, Ohio, USA
EVDL Administrator

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Discussion Starter #3
Re: [EVDL] Vehicle to Ground, comments

----- Original Message -----
From: "David Roden" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Wednesday, October 10, 2007 2:04 PM
Subject: Re: [EVDL] Vehicle to Ground, comments


> On 10 Oct 2007 at 12:05, Bob Rice wrote:
>
>> The setup I use is a 3.5kw
>> jenny backfeeding into my outdoor charge plug for the car/cars
>
> I seldom "yell" but this is one time I think it's warranted.
>
> WARNING. THIS IS A VERY HAZARDOUS PRACTICE.
> Hi David an EVerybody;

Dave brings up some points that I shoulda.Let me go into a few details.

> It is dangerous and illegal for several reasons.
>
> 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.

> 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!! I know that ConnLight and Power linemen GROUND stuff before they
work on it, just in case, I see the stickers on their Trux saying "It isn't
dead , unless it's GROUNDED" So they don't sake chances, anymore. Alota Mc
Mansions come with BIG enough Gennies to seriously backfeed. No Briggs and
Scrapirons here!Yes, a foolproof isolation switch is best, and only way to
go.

> 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
> your
> 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. Now YOU know better? Right?! The
genny would trip out(good thing!) IF you were careless enough to TRY to
backfeed.So forgetabout it! Be super safe. 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. IF you
need to do serious"Plumbing" within your electrical box, this is the only
way to Kill the hot side ahead of the main breaker.OK not for EVerybody. I
was a RR electrician for awile, I told the Electric co that and they were OK
with it. I upgraded my box, with new stuff. By pulling the meter, I took the
sport out of it, and a hellova lot safer, working with the power off!!

> Worse case senerio. A breaker would blow on the genny IF it wasn't in
> phase with the incoming power. But, remember, you ISOLATED the house,
> first. 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!

> Let me repeat this. It is really important.
>
> BACKFEEDING YOUR HOUSE WITHOUT A PROPER LISTED TRANSFER SWITCH CAN KILL
> PEOPLE. In fact, it HAS.
>
> DO NOT DO THIS.

> So IF you aren't clear, as he sez, DON'T DO IT.

> 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! Or, what would be the point of a
> backup gennny? Here in CT and the Least Coast we have WEATHER, like the
> Weather Channel calls it" Extreme Weather"We have been out over a week, at
> times.Usually in temp extremes, cold or hot.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.

Seeya

Bob

> David Roden - Akron, Ohio, USA
> EVDL Administrator
>
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> email address from the webpage http://www.evdl.org/help/ .
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>
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Discussion Starter #4
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

= = = = = = = = = = = = = = = = = = = = = = = = = = = = =
EVDL Information: http://www.evdl.org/help/
= = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Note: mail sent to "evpost" or "etpost" addresses will not
reach me. To send a private message, please obtain my
email address from the webpage http://www.evdl.org/help/ .
= = = = = = = = = = = = = = = = = = = = = = = = = = = = =


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Discussion Starter #5
Re: [EVDL] Vehicle to Ground, comments

David Roden wrote:
> 1. It requires a cable with two male connectors, which could electrocute a
> careless user or child.
>
Just like about 99 million other things. Careless people get killed all
the time by ordinary things. It is impossible to make the world risk free.
> 2. Without a proper transfer switch, it could accidentally backfeed the grid
> and KILL a lineman who is expecting the line to be dead.
>
> Not just make them "p**sed," KILL THEM. As in electrocution. Do I need to
> make that any clearer?
Yes, if your generator can actually take the load of 1000 houses (Or even 2 houses for really local outages) with their lights still turned on, the line voltage could get up to the point of killing a lineman. It is far more likely that the lineman will be killed by an errant lightning strike on the wires somewhere. (Remember outages normally happen during bad weather.)

> 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 your
> or a family member, and setting your house on fire.
>
Explode. Right. So could your TV set. So could your EV plugged into
it's charger.
The 99.999% probability is that you will toast your gensets
regulator/output control, and MAYBE (though highly unlikely) start a
small fire.
> Let me repeat this. It is really important.
>
> BACKFEEDING YOUR HOUSE WITHOUT A PROPER LISTED TRANSFER SWITCH CAN KILL
> PEOPLE. In fact, it HAS.
>
So has driving cars.
> DO NOT DO THIS.
>
> In our litigious society, it is a very bad idea to suggest this practice in
> a public forum.
>
Yup, and there is the real problem. Not real safety violations, but
perceived "I can blame somebody else".

No, I do NOT recommend this practice, but I get really tired of
hysterical screaming about highly unlikely situations and events.

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Discussion Starter #6
Re: [EVDL] Vehicle to Ground, comments

John,
I find your reply unresponsible, because you are
promoting an activity that is likely illegal or
at least you can be considered negligent.

In addition it is unsafe and causes a hazard, even
for people that pay attention, simply by using a
standard product in a non-standard way, causing
surprises.
Any time a safety-related situation causes surprises,
that is bad news. It does not matter whether it is in
traffic or that you deal with high power electrics,
deviating from standard safety practices and using
a product in a way that is guaranteed to give surprises
is a bad thing, especially when it can be avoided at
almost no cost. Don't create a cord with two male
plugs. Instead, make a safe installation. There are
plenty good examples and pretty low cost ones too.

There is no excuse to harm someone or to start a fire.

Some simple examples what can go wrong with a cord
having two male plugs: if someone accidentally plugs
it into two outlets from different breakers but at
the same phase, then you can suddenly pull up to 35 Amp
out of a 15 amp rated outlet, in case the other circuit
has a 20 Amp breaker. Neither outlet nor wiring will be
able to safely supply this current, so you now have
lost the overcurrent protection of your circuit breakers.

The original question dealt with a genny back-feeding
into an outlet, which gives the awkward situation how to
avoid people unplugging either only the genny or only
the indoors outlet and exposing the two prongs that
carry the full AC voltage (against normal expectation).
You could make a lockable box for the indoor outlet, but
this only increases the chance that when power comes back
the genny will be unplugged and the main breaker thrown,
now exposing grid power at the plug lying next to the
genny.

Note that the circuit in which you plug your genny is now
not protected by the house breaker, but only be the
breaker on the genny. That means that if the wiring is
good up to 15 Amp but the genny outlet you are using has a
20 or 30Amp rating, then it is likely you will overload the
wiring in your house where you are backfeeding into.
Even if the genny has a properly rated 15Amp outlet that
you use to plug into a 15 Amp circuit still you can cause
an overload of the wiring:
In the less likely but not impossible case that there is a
grid-connected solar installation which sees the signal
from the genny and finds it within acceptable parameters,
you can now draw 15 Amp from the genny *plus* 15 Amp from
the solar inverter through the house breaker for a total
of 30 Amp out of any outlet on the circuit that the genny
was plugged into, a big fire hazard.

Regarding backfeeding to the transformer and hurting a
lineman: who said you had a whole dubdivision disconnected?
It may be *your* house that was disconnected from the
transformer and when the lineman tries to reconnect your
overhead line and finds it "hot", then he will likely
short-circuit your line first, then cut your line
altogether, from the transformer to the attachment on your
house, remove your meter, let you rot for a couple weeks,
then require a full inspection of your entire house wiring
with signoff by a licensed electrician and mandatory
upgrade of any deviations from code and then be real picky
about anything that they do not like in your system when
they come to reconnect you plus charge you for disconnects
and reconnects..... and I do not blame them.

So, it is your choice if you want to create a safe situation
and install a simple transfer-switch, or create an unsafe
situation and bear the consequences. I see so many ways that
the backfeeding can (and actually has) created a hazard, that
it makes sense to educate people about the ways how to install
their preferred system in a safe way, instead of defending
the bad practice of an unsafe installation.

Cor van de Water
Systems Architect
Proxim Wireless Corporation http://www.proxim.com
Email: [email protected] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [email protected]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Second Life: www.secondlife.com/?u=3b42cb3f4ae249319edb487991c30acb

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of John G. Lussmyer
Sent: Wednesday, October 10, 2007 11:25 AM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Vehicle to Ground, comments

David Roden wrote:
> 1. It requires a cable with two male connectors, which could
> electrocute a careless user or child.
>
Just like about 99 million other things. Careless people get killed all the time by ordinary things. It is impossible to make the world risk free.
> 2. Without a proper transfer switch, it could accidentally backfeed
> the grid and KILL a lineman who is expecting the line to be dead.
>
> Not just make them "p**sed," KILL THEM. As in electrocution. Do I
> need to make that any clearer?
Yes, if your generator can actually take the load of 1000 houses (Or even 2 houses for really local outages) with their lights still turned on, the line voltage could get up to the point of killing a lineman. It is far more likely that the lineman will be killed by an errant lightning strike on the wires somewhere. (Remember outages normally happen during bad weather.)

> 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 your or a family member, and setting your house on fire.
>
Explode. Right. So could your TV set. So could your EV plugged into it's charger.
The 99.999% probability is that you will toast your gensets regulator/output control, and MAYBE (though highly unlikely) start a small fire.
> Let me repeat this. It is really important.
>
> BACKFEEDING YOUR HOUSE WITHOUT A PROPER LISTED TRANSFER SWITCH CAN
> KILL PEOPLE. In fact, it HAS.
>
So has driving cars.
> DO NOT DO THIS.
>
> In our litigious society, it is a very bad idea to suggest this
> practice in a public forum.
>
Yup, and there is the real problem. Not real safety violations, but perceived "I can blame somebody else".

No, I do NOT recommend this practice, but I get really tired of hysterical screaming about highly unlikely situations and events.

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http://lists.sjsu.edu/mailman/listinfo/ev

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