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[EVDL] Vehicle to Ground

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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. The
generator sat on rubber feet, so was not connected to the ground. Now,
instead of a generator, I use the EV's traction pack, which again is a
floating ground. So my two questions are: do I need to tie the
traction pack to ground when I'm using it this way, or is it okay to
leave ground floating? And even more basically, have I broken any NEC
rules wiring the outlets this way?

Bill Dennis

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Hello Bill,

At the generator, the neutral and ground is normally connected together. In
a generator installation, we are require to drive a three foot ground rod
next to the generator and connect the generator ground to this.

As for the EV in providing emergency power to a building, there is a section
in the NEC, that it states, that a electric vehicle shall not be use for
emergency power for a building.

The reason for a standard EV not to be use as a emergency power source, is
that there may be no phase lose protection, low voltage protection, and
transfer switch devices as emergency generators have. You must also have
mechanical protection for your feeder wires to a transfer switch that is
than hard wire into your emergency panel. If you have equipment that have
these safety equipment in it or you design this safety equipment and submit
it to the state electrical board and then you set up a test and demo with
all the instrumentation to prove it works safety for approvable, then you
may get a exception to the NEC rules. This is how we can get some of the
NEC exceptions or changes made.

Roland


----- Original Message -----
From: "Bill Dennis" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Wednesday, October 10, 2007 8:27 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. The
> generator sat on rubber feet, so was not connected to the ground. Now,
> instead of a generator, I use the EV's traction pack, which again is a
> floating ground. So my two questions are: do I need to tie the
> traction pack to ground when I'm using it this way, or is it okay to
> leave ground floating? And even more basically, have I broken any NEC
> rules wiring the outlets this way?
>
> Bill Dennis
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

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That's interesting, Roland. Thanks for the insight. I have a couple
questions, though. What I'm really doing is running the home off of an
inverter that's connected to the car's 12V battery. The 12V battery is
isolated from the traction pack via a DC/DC converter. And as I stated
earlier, the outlets that I use are separate from (not connected to),
the house's main wiring. How does this setup differ from a person who
has a non-grid-tied backup battery bank and inverter in his home that is
used during outages?

Thanks.

Bill Dennis

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I think what Roland is describing is known as a "separately derived
system" and it is appropriate for neutral to be bonded to ground at the
generator. I'm rusty on my code but I seem to remember that an
alternative wiring scheme is available when the bond at the generator doesn't
exist and neutral is shared with the mains circuit. Generator frame grounding is probably
appropriate in either case.

Bob Rice mentioned back-feeding and turning off the main breaker to isolate the house circuits. I would strongly encourage folks NOT to do this: breakers can "leak" current which can lead to interesting experiences when the power comes back on. Don't ask me how I know.... install a properly rated transfer switch.

Roland, can you please provide the NEC reference that prohibits using an EV to provide emergency power? I'd like to read that section.

thanks



----- Original Message ----
From: Roland Wiench <[email protected]>
To: Electric Vehicle Discussion List <[email protected]>
Sent: Wednesday, October 10, 2007 11:44:15 AM
Subject: Re: [EVDL] Vehicle to Ground


Hello Bill,

At the generator, the neutral and ground is normally connected
together. In
a generator installation, we are require to drive a three foot ground
rod
next to the generator and connect the generator ground to this.

As for the EV in providing emergency power to a building, there is a
section
in the NEC, that it states, that a electric vehicle shall not be use
for
emergency power for a building.

The reason for a standard EV not to be use as a emergency power source,
is
that there may be no phase lose protection, low voltage protection, and

transfer switch devices as emergency generators have. You must also
have
mechanical protection for your feeder wires to a transfer switch that
is
than hard wire into your emergency panel. If you have equipment that
have
these safety equipment in it or you design this safety equipment and
submit
it to the state electrical board and then you set up a test and demo
with
all the instrumentation to prove it works safety for approvable, then
you
may get a exception to the NEC rules. This is how we can get some of
the
NEC exceptions or changes made.

Roland


----- Original Message -----
From: "Bill Dennis" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Wednesday, October 10, 2007 8:27 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. The
> generator sat on rubber feet, so was not connected to the ground.
Now,
> instead of a generator, I use the EV's traction pack, which again is
a
> floating ground. So my two questions are: do I need to tie the
> traction pack to ground when I'm using it this way, or is it okay to
> leave ground floating? And even more basically, have I broken any
NEC
> rules wiring the outlets this way?
>
> Bill Dennis
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

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Roland,

As I understand, Dennis is not using and EV to run the house during
power outage. He is using a *battery* of an EV as he would any other
stand alone battery which runs the inverter (which in turn has all the
transfer switches phase sync circuits etc. as per NEC). His battery is
jus happen to be located on the wheels
rather than on the floor as far as NEC is concerned and is no different
as any other back up battery. It's only an energy source in this case.

It can as well declare that he just keeps his *house backup battery* in
his vehicle (as storage location) and occasionally as a side benefit
also runs EV off of it.

Sounds better now?

Victor

Roland Wiench wrote:
> Hello Bill,
>
> At the generator, the neutral and ground is normally connected together. In
> a generator installation, we are require to drive a three foot ground rod
> next to the generator and connect the generator ground to this.
>
> As for the EV in providing emergency power to a building, there is a section
> in the NEC, that it states, that a electric vehicle shall not be use for
> emergency power for a building.
>
> The reason for a standard EV not to be use as a emergency power source, is
> that there may be no phase lose protection, low voltage protection, and
> transfer switch devices as emergency generators have. You must also have
> mechanical protection for your feeder wires to a transfer switch that is
> than hard wire into your emergency panel. If you have equipment that have
> these safety equipment in it or you design this safety equipment and submit
> it to the state electrical board and then you set up a test and demo with
> all the instrumentation to prove it works safety for approvable, then you
> may get a exception to the NEC rules. This is how we can get some of the
> NEC exceptions or changes made.
>
> Roland
>
>
> ----- Original Message -----
> From: "Bill Dennis" <[email protected]>
> To: "Electric Vehicle Discussion List" <[email protected]>
> Sent: Wednesday, October 10, 2007 8:27 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. The
>> generator sat on rubber feet, so was not connected to the ground. Now,
>> instead of a generator, I use the EV's traction pack, which again is a
>> floating ground. So my two questions are: do I need to tie the
>> traction pack to ground when I'm using it this way, or is it okay to
>> leave ground floating? And even more basically, have I broken any NEC
>> rules wiring the outlets this way?
>>
>> Bill Dennis
>>
>> _______________________________________________
>> For subscription options, see
>> http://lists.sjsu.edu/mailman/listinfo/ev
>>
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>
>

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----- Original Message -----
From: "Frank John" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Wednesday, October 10, 2007 12:44 PM
Subject: Re: [EVDL] Vehicle to Ground


>
> I think what Roland is describing is known as a "separately derived
> system" and it is appropriate for neutral to be bonded to ground at the
> generator. I'm rusty on my code but I seem to remember that an
> alternative wiring scheme is available when the bond at the generator
> doesn't
> exist and neutral is shared with the mains circuit. Generator frame
> grounding is probably
> appropriate in either case.
>
> Bob Rice mentioned back-feeding and turning off the main breaker to
> isolate the house circuits. I would strongly encourage folks NOT to do
> this: breakers can "leak" current which can lead to interesting
> experiences when the power comes back on. Don't ask me how I know....
> install a properly rated transfer switch.

Hi EVerybody;
> Good point. But I never had any problems with the "isolated" house. I
> just unplugger thd Jenny and turned on the main breaker to see IF the Real
> Power came back on. When it did, I was plesently surprised, as I never
> knew WHEN it came back!

> Roland, can you please provide the NEC reference that prohibits using an
> EV to provide emergency power? I'd like to read that section.

With powering houses AC Propulsion powered car inverter setup has this
feature. You can provide meaningful amounts of power from yur T zero.Must be
illegal SOMEWHERE? God forbid? I'm sure just running a 'stench chord out to
my Jetta and just plugging it in in the driveway is illegal<g>!?

Pluggin' Along

Bob


>
> thanks
>
>
>
> ----- Original Message ----
> From: Roland Wiench <[email protected]>
> To: Electric Vehicle Discussion List <[email protected]>
> Sent: Wednesday, October 10, 2007 11:44:15 AM
> Subject: Re: [EVDL] Vehicle to Ground
>
>
> Hello Bill,
>
> At the generator, the neutral and ground is normally connected
> together. In
> a generator installation, we are require to drive a three foot ground
> rod
> next to the generator and connect the generator ground to this.
>
> As for the EV in providing emergency power to a building, there is a
> section
> in the NEC, that it states, that a electric vehicle shall not be use
> for
> emergency power for a building.
>
> The reason for a standard EV not to be use as a emergency power source,
> is
> that there may be no phase lose protection, low voltage protection, and
>
> transfer switch devices as emergency generators have. You must also
> have
> mechanical protection for your feeder wires to a transfer switch that
> is
> than hard wire into your emergency panel. If you have equipment that
> have
> these safety equipment in it or you design this safety equipment and
> submit
> it to the state electrical board and then you set up a test and demo
> with
> all the instrumentation to prove it works safety for approvable, then
> you
> may get a exception to the NEC rules. This is how we can get some of
> the
> NEC exceptions or changes made.
>
> Roland
>
>
> ----- Original Message -----
> From: "Bill Dennis" <[email protected]>
> To: "Electric Vehicle Discussion List" <[email protected]>
> Sent: Wednesday, October 10, 2007 8:27 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. The
>> generator sat on rubber feet, so was not connected to the ground.
> Now,
>> instead of a generator, I use the EV's traction pack, which again is
> a
>> floating ground. So my two questions are: do I need to tie the
>> traction pack to ground when I'm using it this way, or is it okay to
>> leave ground floating? And even more basically, have I broken any
> NEC
>> rules wiring the outlets this way?
>>
>> Bill Dennis
>>
>> _______________________________________________
>> For subscription options, see
>> http://lists.sjsu.edu/mailman/listinfo/ev
>>
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>
>
>
>
>
>
>
> ____________________________________________________________________________________
> Need a vacation? Get great deals
> to amazing places on Yahoo! Travel.
> http://travel.yahoo.com/
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>
>
> --
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> Checked by AVG Free Edition.
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On 10 Oct 2007 at 8:27, Bill Dennis wrote:

> do I need to tie the
> traction pack to ground when I'm using it this way, or is it okay to
> leave ground floating? And even more basically, have I broken any NEC
> rules wiring the outlets this way?

I'm pretty sure grounding is required with portable gensets, so I'd assume
that would be the case for other backup power sources. Remember, the main
purpose of the service ground itself is to protect against lightning.

However, I haven't looked into this section of the NEC much. You can get a
copy at your local public library.

I'd say that if you are feeding conventional 120v receptacles with DC,
you're almost certainly violating code and you're definitely asking for
trouble. If someone should accidentally plug an appliance with an induction
motor or a transformer into one of these receptacles, rather bad things
would happen.

Using an EV for backup power is a pretty good idea, IMO. However, to my
knowledge it is a grey area of the NEC. You definitely should use an
approved inverter and transfer switch. Some years ago, Tom Hudson set up
such a system to use the 156v battery in his Solectria Force for backup
power. Maybe he's listening and could provide some details.

Alternatively, you could use extension cords to connect appliances to the
inverter. The NEC does not generally regulate the use of extension cords.

One thing more, don't use the phrase "emergency power" for what you want to
do. From what I've read, that phrase has a specific meaning (I think
related to hospitals, law enforcement, and other official emergency
personnel) that you don't want to invoke. The phrase you want to use for
your research is "backup power."

I agree that it would be a darn shame to have a blackout and not use that
15kWh of energy sitting in your EV's battery.

David Roden - Akron, Ohio, USA
EVDL Administrator

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The NEC article is 625-25. Loss of Primary Source.

Means shall be provided such that upon loss of voltage from the utility or
other electric systems, energy cannot be backfed through the electric
vehicle supply equipment to the premises wiring,

The electric vehicle shall not be permitted to serve as a standby power
supply.

To prevent this back feeding from the EV to the service entrance, the
battery charging equipment is design to prevent this from happening.

If you wanted to do this method of standby power, your charger input power
would have to come from a emergency power panel that we normally install
after a transfer switch than is then connected to a main service panel.

The emergency power panel only feeds those circuits that are design and
limit to the load of the standby power.

The transfer switch will have to be a automatic type, when you loss the
commercial power, it will auto switch the standby power to the emergency
power panels. You will not then get back feed into the commercial power.

The best way is to just plug in the correct size power cables into a onboard
inverter system that has all the safety features directly into the devices
you want keep running, by passing the service entrance.

Roland


----- Original Message -----
From: "Bob Rice" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Wednesday, October 10, 2007 11:12 AM
Subject: Re: [EVDL] Vehicle to Ground


>
> ----- Original Message -----
> From: "Frank John" <[email protected]>
> To: "Electric Vehicle Discussion List" <[email protected]>
> Sent: Wednesday, October 10, 2007 12:44 PM
> Subject: Re: [EVDL] Vehicle to Ground
>
>
> >
> > I think what Roland is describing is known as a "separately derived
> > system" and it is appropriate for neutral to be bonded to ground at the
> > generator. I'm rusty on my code but I seem to remember that an
> > alternative wiring scheme is available when the bond at the generator
> > doesn't
> > exist and neutral is shared with the mains circuit. Generator frame
> > grounding is probably
> > appropriate in either case.
> >
> > Bob Rice mentioned back-feeding and turning off the main breaker to
> > isolate the house circuits. I would strongly encourage folks NOT to do
> > this: breakers can "leak" current which can lead to interesting
> > experiences when the power comes back on. Don't ask me how I know....
> > install a properly rated transfer switch.
>
> Hi EVerybody;
> > Good point. But I never had any problems with the "isolated" house. I
> > just unplugger thd Jenny and turned on the main breaker to see IF the
> > Real
> > Power came back on. When it did, I was plesently surprised, as I never
> > knew WHEN it came back!
>
> > Roland, can you please provide the NEC reference that prohibits using an
> > EV to provide emergency power? I'd like to read that section.
>
> With powering houses AC Propulsion powered car inverter setup has this
> feature. You can provide meaningful amounts of power from yur T zero.Must
> be
> illegal SOMEWHERE? God forbid? I'm sure just running a 'stench chord out
> to
> my Jetta and just plugging it in in the driveway is illegal<g>!?
>
> Pluggin' Along
>
> Bob
>
>
> >
> > thanks
> >
> >
> >
> > ----- Original Message ----
> > From: Roland Wiench <[email protected]>
> > To: Electric Vehicle Discussion List <[email protected]>
> > Sent: Wednesday, October 10, 2007 11:44:15 AM
> > Subject: Re: [EVDL] Vehicle to Ground
> >
> >
> > Hello Bill,
> >
> > At the generator, the neutral and ground is normally connected
> > together. In
> > a generator installation, we are require to drive a three foot ground
> > rod
> > next to the generator and connect the generator ground to this.
> >
> > As for the EV in providing emergency power to a building, there is a
> > section
> > in the NEC, that it states, that a electric vehicle shall not be use
> > for
> > emergency power for a building.
> >
> > The reason for a standard EV not to be use as a emergency power source,
> > is
> > that there may be no phase lose protection, low voltage protection, and
> >
> > transfer switch devices as emergency generators have. You must also
> > have
> > mechanical protection for your feeder wires to a transfer switch that
> > is
> > than hard wire into your emergency panel. If you have equipment that
> > have
> > these safety equipment in it or you design this safety equipment and
> > submit
> > it to the state electrical board and then you set up a test and demo
> > with
> > all the instrumentation to prove it works safety for approvable, then
> > you
> > may get a exception to the NEC rules. This is how we can get some of
> > the
> > NEC exceptions or changes made.
> >
> > Roland
> >
> >
> > ----- Original Message -----
> > From: "Bill Dennis" <[email protected]>
> > To: "Electric Vehicle Discussion List" <[email protected]>
> > Sent: Wednesday, October 10, 2007 8:27 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. The
> >> generator sat on rubber feet, so was not connected to the ground.
> > Now,
> >> instead of a generator, I use the EV's traction pack, which again is
> > a
> >> floating ground. So my two questions are: do I need to tie the
> >> traction pack to ground when I'm using it this way, or is it okay to
> >> leave ground floating? And even more basically, have I broken any
> > NEC
> >> rules wiring the outlets this way?
> >>
> >> Bill Dennis
> >>
> >> _______________________________________________
> >> For subscription options, see
> >> http://lists.sjsu.edu/mailman/listinfo/ev
> >>
> >
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev
> >
> >
> >
> >
> >
> >
> >
> > ____________________________________________________________________________________
> > Need a vacation? Get great deals
> > to amazing places on Yahoo! Travel.
> > http://travel.yahoo.com/
> >
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev
> >
> >
> > --
> > Internal Virus Database is out-of-date.
> > Checked by AVG Free Edition.
> > Version: 7.5.488 / Virus Database: 269.13.28/1023 - Release Date:
> > 9/22/2007 1:27 PM
> >
> >
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
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Thanks, David. I am indeed using an inverter for my backup power. I
don't think a transfer switch is necessary, since these receptacles are
wired totally separately from the house's normal electrical system.

Bill Dennis

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Hello Bill,

That type of wiring is ok, as long as it cannot feed back to commercial
power. It is better than running power cords over the floor.

If you was building a new house and wanted to put this type of circuits in,
a person could have trouble with the building inspectors not understanding
what you are doing. It would be best to use a full automatic system.

Roland


----- Original Message -----
From: "Bill Dennis" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Wednesday, October 10, 2007 9:59 AM
Subject: Re: [EVDL] Vehicle to Ground


> That's interesting, Roland. Thanks for the insight. I have a couple
> questions, though. What I'm really doing is running the home off of an
> inverter that's connected to the car's 12V battery. The 12V battery is
> isolated from the traction pack via a DC/DC converter. And as I stated
> earlier, the outlets that I use are separate from (not connected to),
> the house's main wiring. How does this setup differ from a person who
> has a non-grid-tied backup battery bank and inverter in his home that is
> used during outages?
>
> Thanks.
>
> Bill Dennis
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

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first on the generator it should have it's own ground rod which is bonded to the neutral of the generator . then follow all the normal rules for wiring your house . I am not going to assume that the generator has a circuit breaker so you should have the out put of the generator thru a distribution panel (breaker box ) the feed it to you house following all the normal housing code s for branch circuits under temporary wire art 590 .

now regarding your dc voltage from the EV

the out put of the batteries should go thru a set of dc rated fuses to a invertors the output should go thru a distribution panel that has a ac rated main breaker following the same rules mentioned above for the generator ,

you can at this point tie into the line side of the generators main dist panel IF IT IS NOT RUNNING if the generator is running at the same time that you use the EV then you need to follow the art 590 and use the ground rod of its own the neutral and ground tied in only one place and never after a branch circuit fuse or breaker . you are using the rules for a standby system ( non emergency ) , temporary wiring separately derived systems dc systems , services , branch circuits art 200 ,art 100, art300 and a few others .

realize the insurance company will want to renig if there is a fire and a lic. electrician didn't do the job . and if one did they will go after his bank account after they pay you off . they don't like to suffer any loss and lately my insurance agent told me that they have been pursing whoever wired a commercial place and it was an electrical fire .


----- Original Message -----
From: Bill Dennis<mailto:[email protected]>
To: Electric Vehicle Discussion List<mailto:[email protected]>
Sent: Wednesday, October 10, 2007 9:27 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. The
generator sat on rubber feet, so was not connected to the ground. Now,
instead of a generator, I use the EV's traction pack, which again is a
floating ground. So my two questions are: do I need to tie the
traction pack to ground when I'm using it this way, or is it okay to
leave ground floating? And even more basically, have I broken any NEC
rules wiring the outlets this way?

Bill Dennis

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to ammend my post art 702 covers temporary systems now roland mentioned a 3 ft ground rod I double checked this is art 702.10 and refers to art 250.52 a (all sub paragraphs 1-7 ) it requires a 8 ft ground rod and connection the the grounding electrode system for the residence ! also good to read art 445 (portable generators and art 705 the entire article .
----- Original Message -----
From: FRED JEANETTE MERTENS<mailto:[email protected]>
To: Electric Vehicle Discussion List<mailto:[email protected]>
Sent: Wednesday, October 10, 2007 6:38 PM
Subject: Re: [EVDL] Vehicle to Ground


first on the generator it should have it's own ground rod which is bonded to the neutral of the generator . then follow all the normal rules for wiring your house . I am not going to assume that the generator has a circuit breaker so you should have the out put of the generator thru a distribution panel (breaker box ) the feed it to you house following all the normal housing code s for branch circuits under temporary wire art 590 .

now regarding your dc voltage from the EV

the out put of the batteries should go thru a set of dc rated fuses to a invertors the output should go thru a distribution panel that has a ac rated main breaker following the same rules mentioned above for the generator ,

you can at this point tie into the line side of the generators main dist panel IF IT IS NOT RUNNING if the generator is running at the same time that you use the EV then you need to follow the art 590 and use the ground rod of its own the neutral and ground tied in only one place and never after a branch circuit fuse or breaker . you are using the rules for a standby system ( non emergency ) , temporary wiring separately derived systems dc systems , services , branch circuits art 200 ,art 100, art300 and a few others .

realize the insurance company will want to renig if there is a fire and a lic. electrician didn't do the job . and if one did they will go after his bank account after they pay you off . they don't like to suffer any loss and lately my insurance agent told me that they have been pursing whoever wired a commercial place and it was an electrical fire .


----- Original Message -----
From: Bill Dennis<mailto:[email protected]<mailto:[email protected]>>
To: Electric Vehicle Discussion List<mailto:[email protected]<mailto:[email protected]>>
Sent: Wednesday, October 10, 2007 9:27 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. The
generator sat on rubber feet, so was not connected to the ground. Now,
instead of a generator, I use the EV's traction pack, which again is a
floating ground. So my two questions are: do I need to tie the
traction pack to ground when I'm using it this way, or is it okay to
leave ground floating? And even more basically, have I broken any NEC
rules wiring the outlets this way?

Bill Dennis

_______________________________________________
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what you are saying is correct if the branch circuits are tied in any way to the UNGROUNDED conductors . if they are not then you can go to a fused disconnect to a invertors to a ac distribution panel to the standby system remember the orginal post was not a interactive system !!! I belive this makes a difference
----- Original Message -----
From: Roland Wiench<mailto:[email protected]>
To: Electric Vehicle Discussion List<mailto:[email protected]>
Sent: Wednesday, October 10, 2007 12:57 PM
Subject: Re: [EVDL] Vehicle to Ground


The NEC article is 625-25. Loss of Primary Source.

Means shall be provided such that upon loss of voltage from the utility or
other electric systems, energy cannot be backfed through the electric
vehicle supply equipment to the premises wiring,

The electric vehicle shall not be permitted to serve as a standby power
supply.

To prevent this back feeding from the EV to the service entrance, the
battery charging equipment is design to prevent this from happening.

If you wanted to do this method of standby power, your charger input power
would have to come from a emergency power panel that we normally install
after a transfer switch than is then connected to a main service panel.

The emergency power panel only feeds those circuits that are design and
limit to the load of the standby power.

The transfer switch will have to be a automatic type, when you loss the
commercial power, it will auto switch the standby power to the emergency
power panels. You will not then get back feed into the commercial power.

The best way is to just plug in the correct size power cables into a onboard
inverter system that has all the safety features directly into the devices
you want keep running, by passing the service entrance.

Roland


----- Original Message -----
From: "Bob Rice" <[email protected]<mailto:[email protected]>>
To: "Electric Vehicle Discussion List" <[email protected]<mailto:[email protected]>>
Sent: Wednesday, October 10, 2007 11:12 AM
Subject: Re: [EVDL] Vehicle to Ground


>
> ----- Original Message -----
> From: "Frank John" <[email protected]<mailto:[email protected]>>
> To: "Electric Vehicle Discussion List" <[email protected]<mailto:[email protected]>>
> Sent: Wednesday, October 10, 2007 12:44 PM
> Subject: Re: [EVDL] Vehicle to Ground
>
>
> >
> > I think what Roland is describing is known as a "separately derived
> > system" and it is appropriate for neutral to be bonded to ground at the
> > generator. I'm rusty on my code but I seem to remember that an
> > alternative wiring scheme is available when the bond at the generator
> > doesn't
> > exist and neutral is shared with the mains circuit. Generator frame
> > grounding is probably
> > appropriate in either case.
> >
> > Bob Rice mentioned back-feeding and turning off the main breaker to
> > isolate the house circuits. I would strongly encourage folks NOT to do
> > this: breakers can "leak" current which can lead to interesting
> > experiences when the power comes back on. Don't ask me how I know....
> > install a properly rated transfer switch.
>
> Hi EVerybody;
> > Good point. But I never had any problems with the "isolated" house. I
> > just unplugger thd Jenny and turned on the main breaker to see IF the
> > Real
> > Power came back on. When it did, I was plesently surprised, as I never
> > knew WHEN it came back!
>
> > Roland, can you please provide the NEC reference that prohibits using an
> > EV to provide emergency power? I'd like to read that section.
>
> With powering houses AC Propulsion powered car inverter setup has this
> feature. You can provide meaningful amounts of power from yur T zero.Must
> be
> illegal SOMEWHERE? God forbid? I'm sure just running a 'stench chord out
> to
> my Jetta and just plugging it in in the driveway is illegal<g>!?
>
> Pluggin' Along
>
> Bob
>
>
> >
> > thanks
> >
> >
> >
> > ----- Original Message ----
> > From: Roland Wiench <[email protected]<mailto:[email protected]>>
> > To: Electric Vehicle Discussion List <[email protected]<mailto:[email protected]>>
> > Sent: Wednesday, October 10, 2007 11:44:15 AM
> > Subject: Re: [EVDL] Vehicle to Ground
> >
> >
> > Hello Bill,
> >
> > At the generator, the neutral and ground is normally connected
> > together. In
> > a generator installation, we are require to drive a three foot ground
> > rod
> > next to the generator and connect the generator ground to this.
> >
> > As for the EV in providing emergency power to a building, there is a
> > section
> > in the NEC, that it states, that a electric vehicle shall not be use
> > for
> > emergency power for a building.
> >
> > The reason for a standard EV not to be use as a emergency power source,
> > is
> > that there may be no phase lose protection, low voltage protection, and
> >
> > transfer switch devices as emergency generators have. You must also
> > have
> > mechanical protection for your feeder wires to a transfer switch that
> > is
> > than hard wire into your emergency panel. If you have equipment that
> > have
> > these safety equipment in it or you design this safety equipment and
> > submit
> > it to the state electrical board and then you set up a test and demo
> > with
> > all the instrumentation to prove it works safety for approvable, then
> > you
> > may get a exception to the NEC rules. This is how we can get some of
> > the
> > NEC exceptions or changes made.
> >
> > Roland
> >
> >
> > ----- Original Message -----
> > From: "Bill Dennis" <[email protected]<mailto:[email protected]>>
> > To: "Electric Vehicle Discussion List" <[email protected]<mailto:[email protected]>>
> > Sent: Wednesday, October 10, 2007 8:27 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. The
> >> generator sat on rubber feet, so was not connected to the ground.
> > Now,
> >> instead of a generator, I use the EV's traction pack, which again is
> > a
> >> floating ground. So my two questions are: do I need to tie the
> >> traction pack to ground when I'm using it this way, or is it okay to
> >> leave ground floating? And even more basically, have I broken any
> > NEC
> >> rules wiring the outlets this way?
> >>
> >> Bill Dennis
> >>
> >> _______________________________________________
> >> For subscription options, see
> >> http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
> >>
> >
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
> >
> >
> >
> >
> >
> >
> >
> > ____________________________________________________________________________________
> > Need a vacation? Get great deals
> > to amazing places on Yahoo! Travel.
> > http://travel.yahoo.com/<http://travel.yahoo.com/>
> >
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
> >
> >
> > --
> > Internal Virus Database is out-of-date.
> > Checked by AVG Free Edition.
> > Version: 7.5.488 / Virus Database: 269.13.28/1023 - Release Date:
> > 9/22/2007 1:27 PM
> >
> >
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
>

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by the way Roland I really like your answers to posts they are very good and always safe . this one made me Dig a little .
----- Original Message -----
From: Roland Wiench<mailto:[email protected]>
To: Electric Vehicle Discussion List<mailto:[email protected]>
Sent: Wednesday, October 10, 2007 12:57 PM
Subject: Re: [EVDL] Vehicle to Ground


The NEC article is 625-25. Loss of Primary Source.

Means shall be provided such that upon loss of voltage from the utility or
other electric systems, energy cannot be backfed through the electric
vehicle supply equipment to the premises wiring,

The electric vehicle shall not be permitted to serve as a standby power
supply.

To prevent this back feeding from the EV to the service entrance, the
battery charging equipment is design to prevent this from happening.

If you wanted to do this method of standby power, your charger input power
would have to come from a emergency power panel that we normally install
after a transfer switch than is then connected to a main service panel.

The emergency power panel only feeds those circuits that are design and
limit to the load of the standby power.

The transfer switch will have to be a automatic type, when you loss the
commercial power, it will auto switch the standby power to the emergency
power panels. You will not then get back feed into the commercial power.

The best way is to just plug in the correct size power cables into a onboard
inverter system that has all the safety features directly into the devices
you want keep running, by passing the service entrance.

Roland


----- Original Message -----
From: "Bob Rice" <[email protected]<mailto:[email protected]>>
To: "Electric Vehicle Discussion List" <[email protected]<mailto:[email protected]>>
Sent: Wednesday, October 10, 2007 11:12 AM
Subject: Re: [EVDL] Vehicle to Ground


>
> ----- Original Message -----
> From: "Frank John" <[email protected]<mailto:[email protected]>>
> To: "Electric Vehicle Discussion List" <[email protected]<mailto:[email protected]>>
> Sent: Wednesday, October 10, 2007 12:44 PM
> Subject: Re: [EVDL] Vehicle to Ground
>
>
> >
> > I think what Roland is describing is known as a "separately derived
> > system" and it is appropriate for neutral to be bonded to ground at the
> > generator. I'm rusty on my code but I seem to remember that an
> > alternative wiring scheme is available when the bond at the generator
> > doesn't
> > exist and neutral is shared with the mains circuit. Generator frame
> > grounding is probably
> > appropriate in either case.
> >
> > Bob Rice mentioned back-feeding and turning off the main breaker to
> > isolate the house circuits. I would strongly encourage folks NOT to do
> > this: breakers can "leak" current which can lead to interesting
> > experiences when the power comes back on. Don't ask me how I know....
> > install a properly rated transfer switch.
>
> Hi EVerybody;
> > Good point. But I never had any problems with the "isolated" house. I
> > just unplugger thd Jenny and turned on the main breaker to see IF the
> > Real
> > Power came back on. When it did, I was plesently surprised, as I never
> > knew WHEN it came back!
>
> > Roland, can you please provide the NEC reference that prohibits using an
> > EV to provide emergency power? I'd like to read that section.
>
> With powering houses AC Propulsion powered car inverter setup has this
> feature. You can provide meaningful amounts of power from yur T zero.Must
> be
> illegal SOMEWHERE? God forbid? I'm sure just running a 'stench chord out
> to
> my Jetta and just plugging it in in the driveway is illegal<g>!?
>
> Pluggin' Along
>
> Bob
>
>
> >
> > thanks
> >
> >
> >
> > ----- Original Message ----
> > From: Roland Wiench <[email protected]<mailto:[email protected]>>
> > To: Electric Vehicle Discussion List <[email protected]<mailto:[email protected]>>
> > Sent: Wednesday, October 10, 2007 11:44:15 AM
> > Subject: Re: [EVDL] Vehicle to Ground
> >
> >
> > Hello Bill,
> >
> > At the generator, the neutral and ground is normally connected
> > together. In
> > a generator installation, we are require to drive a three foot ground
> > rod
> > next to the generator and connect the generator ground to this.
> >
> > As for the EV in providing emergency power to a building, there is a
> > section
> > in the NEC, that it states, that a electric vehicle shall not be use
> > for
> > emergency power for a building.
> >
> > The reason for a standard EV not to be use as a emergency power source,
> > is
> > that there may be no phase lose protection, low voltage protection, and
> >
> > transfer switch devices as emergency generators have. You must also
> > have
> > mechanical protection for your feeder wires to a transfer switch that
> > is
> > than hard wire into your emergency panel. If you have equipment that
> > have
> > these safety equipment in it or you design this safety equipment and
> > submit
> > it to the state electrical board and then you set up a test and demo
> > with
> > all the instrumentation to prove it works safety for approvable, then
> > you
> > may get a exception to the NEC rules. This is how we can get some of
> > the
> > NEC exceptions or changes made.
> >
> > Roland
> >
> >
> > ----- Original Message -----
> > From: "Bill Dennis" <[email protected]<mailto:[email protected]>>
> > To: "Electric Vehicle Discussion List" <[email protected]<mailto:[email protected]>>
> > Sent: Wednesday, October 10, 2007 8:27 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. The
> >> generator sat on rubber feet, so was not connected to the ground.
> > Now,
> >> instead of a generator, I use the EV's traction pack, which again is
> > a
> >> floating ground. So my two questions are: do I need to tie the
> >> traction pack to ground when I'm using it this way, or is it okay to
> >> leave ground floating? And even more basically, have I broken any
> > NEC
> >> rules wiring the outlets this way?
> >>
> >> Bill Dennis
> >>
> >> _______________________________________________
> >> For subscription options, see
> >> http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
> >>
> >
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
> >
> >
> >
> >
> >
> >
> >
> > ____________________________________________________________________________________
> > Need a vacation? Get great deals
> > to amazing places on Yahoo! Travel.
> > http://travel.yahoo.com/<http://travel.yahoo.com/>
> >
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
> >
> >
> > --
> > Internal Virus Database is out-of-date.
> > Checked by AVG Free Edition.
> > Version: 7.5.488 / Virus Database: 269.13.28/1023 - Release Date:
> > 9/22/2007 1:27 PM
> >
> >
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
>

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Hello Fred,

This ground rod length of 8 foot is true for a permanent installation at a
residence or in case of some commercial buildings we have to use 10 foot by
3/4 inch ground rods.

Some small portable generators come with a 3-foot grounding kit. Sometimes
we use them for lightning protection. Other wise just the frame of the
generator shall be permitted to serve as a grounding electrode if it power
cord connected and the ground wires are only bonded to the generator frame,
not the neutral wires. Article 250-34.

Roland



Roland


----- Original Message -----
From: "FRED JEANETTE MERTENS" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Wednesday, October 10, 2007 6:04 PM
Subject: Re: [EVDL] Vehicle to Ground


> to ammend my post art 702 covers temporary systems now roland mentioned
> a 3 ft ground rod I double checked this is art 702.10 and refers to art
> 250.52 a (all sub paragraphs 1-7 ) it requires a 8 ft ground rod and
> connection the the grounding electrode system for the residence ! also
> good to read art 445 (portable generators and art 705 the entire article
> .
> ----- Original Message -----
> From: FRED JEANETTE MERTENS<mailto:[email protected]>
> To: Electric Vehicle Discussion List<mailto:[email protected]>
> Sent: Wednesday, October 10, 2007 6:38 PM
> Subject: Re: [EVDL] Vehicle to Ground
>
>
> first on the generator it should have it's own ground rod which is
> bonded to the neutral of the generator . then follow all the normal rules
> for wiring your house . I am not going to assume that the generator has a
> circuit breaker so you should have the out put of the generator thru a
> distribution panel (breaker box ) the feed it to you house following
> all the normal housing code s for branch circuits under temporary wire
> art 590 .
>
> now regarding your dc voltage from the EV
>
> the out put of the batteries should go thru a set of dc rated fuses to
> a invertors the output should go thru a distribution panel that has a ac
> rated main breaker following the same rules mentioned above for the
> generator ,
>
> you can at this point tie into the line side of the generators main dist
> panel IF IT IS NOT RUNNING if the generator is running at the same time
> that you use the EV then you need to follow the art 590 and use the
> ground rod of its own the neutral and ground tied in only one place and
> never after a branch circuit fuse or breaker . you are using the rules
> for a standby system ( non emergency ) , temporary wiring separately
> derived systems dc systems , services , branch circuits art 200 ,art 100,
> art300 and a few others .
>
> realize the insurance company will want to renig if there is a fire and
> a lic. electrician didn't do the job . and if one did they will go after
> his bank account after they pay you off . they don't like to suffer any
> loss and lately my insurance agent told me that they have been pursing
> whoever wired a commercial place and it was an electrical fire .
>
>
> ----- Original Message -----
> From: Bill
> Dennis<mailto:[email protected]<mailto:[email protected]>>
> To: Electric Vehicle Discussion
> List<mailto:[email protected]<mailto:[email protected]>>
> Sent: Wednesday, October 10, 2007 9:27 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. The
> generator sat on rubber feet, so was not connected to the ground.
> Now,
> instead of a generator, I use the EV's traction pack, which again is a
> floating ground. So my two questions are: do I need to tie the
> traction pack to ground when I'm using it this way, or is it okay to
> leave ground floating? And even more basically, have I broken any NEC
> rules wiring the outlets this way?
>
> Bill Dennis
>
> _______________________________________________
> For subscription options, see
>
> http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>>
> _______________________________________________
> For subscription options, see
>
> http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
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I want to point out that the NEC is not the law. Its an *independent*
organization that codes electrical recommendations. To get a complete
answer of what is required in your area you must look at the local
electrical codes. Likely the NEC Articles are substantial part of it,
but there may be specific alterations or deletions and the version
used in your location may not be the current version. When different
you need to follow local code (that will get you through inspection.)

Paul Gooch


Roland Wiench wrote:

> This ground rod length of 8 foot is true for a permanent
> installation at a
> residence or in case of some commercial buildings we have to use 10
> foot by
> 3/4 inch ground rods.
>
> Some small portable generators come with a 3-foot grounding kit.
> Sometimes
> we use them for lightning protection. Other wise just the frame of
> the
> generator shall be permitted to serve as a grounding electrode if
> it power
> cord connected and the ground wires are only bonded to the
> generator frame,
> not the neutral wires. Article 250-34.

_______________________________________________
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