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  #1   Report Post  
 
Posts: n/a
Default Backfeed generator through dryer outlet?

Let me start by saying I know this is very dangerous and I don't plan
on doing it (I have a new generator and new uninstalled transfer
switch) so save your flames. I plan on installing my transfer switch
when I get some time in the next month or two.

I read a post suggesting that in a power outage, you could flip your
main breaker off to prevent anything going to the lines and killing a
line worker, and use a suicide cord from your generator to you clothes
dryer outlet (240 vac) and then your main panel would serve as your
switch for what circuits are using the generator--and that this would
power both 240 and 120 outlets.

As dangerous as this is, is this even possible?

  #2   Report Post  
louie
 
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Default Backfeed generator through dryer outlet?

Yes, but not recommended because of the potential danger involved (both
to the homeowner and to the line workers in the event someone forgets
to turn off the main). You would be limited by the size of the breaker
you are feeding through (in this case the clothes dryer), but it would
make your whole panel live just as if it were being fed through the
main.

  #3   Report Post  
Jim & Lil
 
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Default Backfeed generator through dryer outlet?


wrote in message
ups.com...
Let me start by saying I know this is very dangerous and I don't plan
on doing it (I have a new generator and new uninstalled transfer
switch) so save your flames. I plan on installing my transfer switch
when I get some time in the next month or two.

I read a post suggesting that in a power outage, you could flip your
main breaker off to prevent anything going to the lines and killing a
line worker, and use a suicide cord from your generator to you clothes
dryer outlet (240 vac) and then your main panel would serve as your
switch for what circuits are using the generator--and that this would
power both 240 and 120 outlets.

As dangerous as this is, is this even possible?

I had asked this hypothetical question a few years ago and glad you
mentioned the flames...LOL...Cause I sure got my fair share of those asking
that question.. One thing that was constructive in my replies is that even
with your main braker shut off, you may be still feeding power down the line
via the neutral wire....another constructive reply was to also ask in
alt.energy.homepower They are a very knowledgable group... Hope that was
of some help.... Jim


  #5   Report Post  
 
Posts: n/a
Default Backfeed generator through dryer outlet?

Jim & Lil wrote:

wrote:


I read a post suggesting that in a power outage, you could flip your
main breaker off to prevent anything going to the lines and killing a
line worker, and use a suicide cord from your generator to you clothes
dryer outlet (240 vac) and then your main panel would serve as your
switch for what circuits are using the generator--and that this would
power both 240 and 120 outlets.

As dangerous as this is, is this even possible?


Sounds possible, and safe, unless you guzzle too much beer. You might
hang a big tag on the generator that says "Turn off the main breaker!"

...One thing that was constructive in my replies is that even with your
main braker shut off, you may be still feeding power down the line via
the neutral wire...


That seems a very unlikely hazard, since it requires 1) a grid power
failure, and 2) a hot to neutral connection that doesn't blow your own
breaker, and 3) a neutral wire that doesn't end up attached to ground
somewhere outside your house.

Nick



  #6   Report Post  
BobG
 
Posts: n/a
Default Backfeed generator through dryer outlet?

Also, the line splicers ground the lines they're splicing. That will
make your generator extremely unhappy for a few seconds should you
forget to pull the main.

  #7   Report Post  
JoeSixPack
 
Posts: n/a
Default Backfeed generator through dryer outlet?


wrote in message
...
Jim & Lil wrote:

wrote:


I read a post suggesting that in a power outage, you could flip your
main breaker off to prevent anything going to the lines and killing a
line worker, and use a suicide cord from your generator to you clothes
dryer outlet (240 vac) and then your main panel would serve as your
switch for what circuits are using the generator--and that this would
power both 240 and 120 outlets.

As dangerous as this is, is this even possible?


Sounds possible, and safe, unless you guzzle too much beer. You might
hang a big tag on the generator that says "Turn off the main breaker!"

...One thing that was constructive in my replies is that even with your
main braker shut off, you may be still feeding power down the line via
the neutral wire...


That seems a very unlikely hazard, since it requires 1) a grid power
failure, and 2) a hot to neutral connection that doesn't blow your own
breaker, and 3) a neutral wire that doesn't end up attached to ground
somewhere outside your house.

Nick



  #9   Report Post  
JoeSixPack
 
Posts: n/a
Default Backfeed generator through dryer outlet?


wrote in message
...
Jim & Lil wrote:

wrote:


I read a post suggesting that in a power outage, you could flip your
main breaker off to prevent anything going to the lines and killing a
line worker, and use a suicide cord from your generator to you clothes
dryer outlet (240 vac) and then your main panel would serve as your
switch for what circuits are using the generator--and that this would
power both 240 and 120 outlets.

As dangerous as this is, is this even possible?


Sounds possible, and safe, unless you guzzle too much beer. You might
hang a big tag on the generator that says "Turn off the main breaker!"

...One thing that was constructive in my replies is that even with your
main braker shut off, you may be still feeding power down the line via
the neutral wire...


That seems a very unlikely hazard, since it requires 1) a grid power
failure, and 2) a hot to neutral connection that doesn't blow your own
breaker, and 3) a neutral wire that doesn't end up attached to ground
somewhere outside your house.

Nick



  #10   Report Post  
Toller
 
Posts: n/a
Default Backfeed generator through dryer outlet?

I've done it. Lots of other people have also. But there actually have been
fatalities as a result of doing it.

I put in a transfer switch because it just made me uncomfortable.




  #11   Report Post  
JoeSixPack
 
Posts: n/a
Default Backfeed generator through dryer outlet?


wrote in message
...
Jim & Lil wrote:

wrote:


I read a post suggesting that in a power outage, you could flip your
main breaker off to prevent anything going to the lines and killing a
line worker, and use a suicide cord from your generator to you clothes
dryer outlet (240 vac) and then your main panel would serve as your
switch for what circuits are using the generator--and that this would
power both 240 and 120 outlets.

As dangerous as this is, is this even possible?


Sounds possible, and safe, unless you guzzle too much beer. You might
hang a big tag on the generator that says "Turn off the main breaker!"


For the added piece of mind, a generator/main selector switch is a modest
investment.
Power failures can result in stress and confusion that make things like
leaving the main breaker on a virtual certtainty at some point. Why take the
chance to save a few bucks.


...One thing that was constructive in my replies is that even with your
main braker shut off, you may be still feeding power down the line via
the neutral wire...


That seems a very unlikely hazard, since it requires 1) a grid power
failure, and 2) a hot to neutral connection that doesn't blow your own
breaker, and 3) a neutral wire that doesn't end up attached to ground
somewhere outside your house.

Nick



Unless I'm mistaken, some 240V outlets do not have the neutral wire
connected to the mains. Only a ground wire, which is insufficient to power
the 120V circuits. This would result in 240 service only in the house
wiring, when feeding in from a generator.


  #12   Report Post  
 
Posts: n/a
Default Backfeed generator through dryer outlet?

I'm surprised nobody's mentioned being sure to have (2) hot leads and
neutral, so you can power 117v circuits.

I've done this sort of thing many times over the years, but via single
117v 15a or 20a branch circuit. Main opened first, ditto all breakers
(which are accurately labelled as to which load). Of course circuit is
chosen so as to power selected "phase" which luckily has covered the
necessary loads. Then one breaker at a time on, and maybe rotated as
necessary. (Refrigerator does not need power 100% of time, nor does
furnace blower. Yada, yada.)

At a friend's house, opening main breaker one time, caused it to fail
to close forever more. Which sped up replacement.

HTH,
J

  #13   Report Post  
 
Posts: n/a
Default Backfeed generator through dryer outlet?

Toller wrote:

I've done it. Lots of other people have also. But there actually have been
fatalities as a result of doing it.


I've heard that's never actually happened. Can you name one?

Nick

  #14   Report Post  
Pete C.
 
Posts: n/a
Default Backfeed generator through dryer outlet?

JoeSixPack wrote:

wrote in message
...
Jim & Lil wrote:

wrote:


I read a post suggesting that in a power outage, you could flip your
main breaker off to prevent anything going to the lines and killing a
line worker, and use a suicide cord from your generator to you clothes
dryer outlet (240 vac) and then your main panel would serve as your
switch for what circuits are using the generator--and that this would
power both 240 and 120 outlets.

As dangerous as this is, is this even possible?


Sounds possible, and safe, unless you guzzle too much beer. You might
hang a big tag on the generator that says "Turn off the main breaker!"


For the added piece of mind, a generator/main selector switch is a modest
investment.
Power failures can result in stress and confusion that make things like
leaving the main breaker on a virtual certtainty at some point. Why take the
chance to save a few bucks.


...One thing that was constructive in my replies is that even with your
main braker shut off, you may be still feeding power down the line via
the neutral wire...


That seems a very unlikely hazard, since it requires 1) a grid power
failure, and 2) a hot to neutral connection that doesn't blow your own
breaker, and 3) a neutral wire that doesn't end up attached to ground
somewhere outside your house.

Nick


Unless I'm mistaken, some 240V outlets do not have the neutral wire
connected to the mains. Only a ground wire, which is insufficient to power
the 120V circuits. This would result in 240 service only in the house
wiring, when feeding in from a generator.


You are partially mistaken. Some older 240v outlets indeed do not have a
neutral connection, however newer ones do (code change). Since the
ground and neutral are required by code to be bonded at the service
entrance panel you will get the same functionality even if you're
feeding an older dryer outlet with no dedicated neutral i.e. using the
ground as a neutral.

The ground on the circuit may be a gauge lighter wire than the main
conductors which would limit your circuit capacity if you had a large
generator (~7kw or larger), but most people doing a dryer outlet
backfeed will have 5kw or smaller generators in which case even a
reduced gauge ground on a dryer outlet has adequate capacity.

Additionally since not only are the ground and neutral requited by code
to be bonded at the service entrance panel, there is also a required
ground rod (or two) connection at the service entrance panel which makes
it all but impossible to backfeed any power down the line if the main
breaker is off. The additional grounding of the utility system neutral
every few poles provides yet another level of protection.

The true risks are 1. Forgetting to shut off the main breaker, and 2.
Forgetting the danger of the double-male "suicide" cord and proper
connection / disconnection sequences.

Pete C.
  #15   Report Post  
Toller
 
Posts: n/a
Default Backfeed generator through dryer outlet?


wrote in message
...
Toller wrote:

I've done it. Lots of other people have also. But there actually have
been
fatalities as a result of doing it.


I've heard that's never actually happened. Can you name one?

A couple years ago I asked the same question. Someone came up with at least
one example.
It does seem unlikely; if your main breaker is closed, your genny should
stall immediately when it tries to power the neighborhood. The only way you
could kill a lineman is if YOUR line if down and he is fixing it, or if (and
even this is a reach) you plugged in while he what handling a nearby line.
Of course, even then he is supposed to be protected from live wires by
insulation.

Still, a transfer switch avoids the embarrassing chance of continuing to run
on generator after you have power back. I did that for an hour once before
someone called me.




  #17   Report Post  
JoeSixPack
 
Posts: n/a
Default Backfeed generator through dryer outlet?


wrote in message
...
On Thu, 27 Oct 2005 11:31:38 -0600, "Jim & Lil"
wrote:


wrote in message
roups.com...



I had asked this hypothetical question a few years ago and glad you
mentioned the flames...LOL...Cause I sure got my fair share of those
asking
that question.. One thing that was constructive in my replies is that even
with your main braker shut off, you may be still feeding power down the
line
via the neutral wire....another constructive reply was to also ask in
alt.energy.homepower They are a very knowledgable group... Hope that was
of some help.... Jim


I'd like an explanation of how you could feed power down line thru the
neutral?


If the neutral isn't properly grounded at the service tap, it is forced back
up the line to the next good grounding point. Not a serious danger unless
people or equipment are connected in parallel to this defacto circuit. I
think it's possible that someone in an adjacent residence could be at risk
of getting a shock by being connected to both a good ground and the ground
terminal of an outlet, if the resistence to ground is greater at their
junction box. An example might be having one hand on a water tap and the
other on the metal case of an appliance with a 3-prong plug, and feeling a
tingle of current that originated from your neighbor's generator.


  #18   Report Post  
JoeSixPack
 
Posts: n/a
Default Backfeed generator through dryer outlet?


"Toller" wrote in message
...

wrote in message
...
Toller wrote:



Still, a transfer switch avoids the embarrassing chance of continuing to
run on generator after you have power back. I did that for an hour once
before someone called me.


Couldn't you wire in a light on the power main side to tell you when the
power is back on?


  #19   Report Post  
Solar Flare
 
Posts: n/a
Default Backfeed generator through dryer outlet?

When they turn the power back on you can generate your own gasoline as your unit
regenerates. This can be syphoned off for your car usage at a very cheap rate.

"BobG" wrote in message
oups.com...
Also, the line splicers ground the lines they're splicing. That will
make your generator extremely unhappy for a few seconds should you
forget to pull the main.



  #20   Report Post  
Solar Flare
 
Posts: n/a
Default Backfeed generator through dryer outlet?

Yup. with the main switch open

"JoeSixPack" wrote in message
news:jKd8f.49301$yS6.3894@clgrps12...

"Toller" wrote in message
...

wrote in message
...
Toller wrote:



Still, a transfer switch avoids the embarrassing chance of continuing to
run on generator after you have power back. I did that for an hour once
before someone called me.


Couldn't you wire in a light on the power main side to tell you when the
power is back on?






  #21   Report Post  
Solar Flare
 
Posts: n/a
Default Backfeed generator through dryer outlet?

According to the OSHA rules of Ontario. Massive mistakes were made and
management would be held responsible and probably jailed for lying about the
state of the lines in each case.

The generator hookup people would have their pee-pees slapped but no where near
the foreman and the upper people for the deaths.

Now one was in Peurto Rico and there are so many more waiting for jobs that one
isn't gonna' be noticed.

Wire a tranfer switch box in with 4 or 6 circuits you want to be backed up and a
proper plug on the damn thing.
Don't play with people's safety or your own. Your unit coming becoming energized
may not be fun either unless you have money to burn.

The meter base does not isolate the neutral. Unless you have a fault in your
home it won't be a problem.

"Tony Wesley" wrote in message
oups.com...
wrote:
Toller wrote:
I've done it. Lots of other people have also. But there actually have

been
fatalities as a result of doing it.


I've heard that's never actually happened.


I've heard the moon is made of green cheese

Can you name one?




http://groups.google.com/group/alt.e...99ee436?hl=en&



http://groups.google.com/group/alt.e...04bb4bc?hl=en&



  #22   Report Post  
Veritas
 
Posts: n/a
Default Backfeed generator through dryer outlet?

"Jim & Lil" wrote:
... One thing that was constructive in my replies is that even
with your main braker shut off, you may be still feeding power down the line
via the neutral wire..


Most transfer switches do not switch the neutral wire anyway. However,
if your generator and your panel is properly grounded, it should be
almost impossible to energize the neutral enough to do harm, even
without a real transfer switch.

Having said that, obviously, a transfer switch is the only way to go.
Backfeeding an outlet is dangerous and violates the NEC.
  #23   Report Post  
Steve Kraus
 
Posts: n/a
Default Backfeed generator through dryer outlet?

It does seem unlikely; if your main breaker is closed, your genny
should stall immediately when it tries to power the neighborhood.


I think unless you have some sort of huge generator the load presented by
the outside world will look to the generator as pretty much a short to
ground. It would really have to be a situation where the power outage
resulted in you and your immediate neighbors being islanded. Where I live
there are 10 houses on the same pole transformer and even if that were
isolated I doubt my 4.4 kW machine could pull that load. Maybe if it were
the middle of the night and everyone's fridge just happened to finish
cycling before the power went out and and and... I think the risk is
nearly zip. But for safety to your machine more so than risk to any
lineman it might not be a bad idea to attach a reminder sign to your double
male cable or adaptor or whatever you do this with: TURN OFF MAIN BREAKER
BEFORE USING
  #24   Report Post  
Chris Lewis
 
Posts: n/a
Default Backfeed generator through dryer outlet?

According to :

As dangerous as this is, is this even possible?


Of course. 4 wire 240V is 4 wire 240V, and breakers don't care
which terminals are the innie and which are the outie ;-)

We were installing a new main panel, and just when we wanted
to transfer the feed, the local power company went on strike.
Out of necessity (because so much had been transferred to the
new panel), we ended up temporarily backfeeding the new main
panel thru its dryer circuit from the old main's dryer circuit.
[The new main didn't have a meter installed nor the main
feed of course.]

During the great ice storm, a friend and I helped a muncipality
out by doing inspections of generator installations. One of them
(installed by a professional electrician) wired the generator
directly into the panel's backplane (they were lucky, they
just got their power back, and all we did was remove the
backfeed and reestablish the real feed). The main breaker
was wired open.

During the same ice storm, we spliced a 100Kw generator directly
into a main panel (after physically disconnecting the line
feed). [This was at the municipal works garage, and became
a base for emergency crews, road clearance, and included the
army's food/fuel distribution center.]

In an emergency, you gotta do what you gotta do. However,
if you do have to do this, you have to do whatever you can
to make it safe (ie: wire or padlock or physically disconnect the
main). Secondly, if you are preparing for an emergency
_before_ the emergency takes place, do it right. Installing
outlets and obtaining a suicide cord is not right.

[Theoretically, an illegal backfeed can earn you a $6000 fine
here. Worse if you hurt someone.]
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.
  #25   Report Post  
Chris Lewis
 
Posts: n/a
Default Backfeed generator through dryer outlet?

According to Steve Kraus :
It does seem unlikely; if your main breaker is closed, your genny
should stall immediately when it tries to power the neighborhood.


I think unless you have some sort of huge generator the load presented by
the outside world will look to the generator as pretty much a short to
ground.


Precisely.

A friend of a friend suicide-corded his generator into his house,
and the generator promptly smoked within seconds of firing up.

He forgot the main breaker.

[It managed to fire up because the generator is automatically
not connected during startup, and "engages" when the motor is
up to speed. At which point it started belching smoke and stalled
out.]
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.


  #26   Report Post  
Me
 
Posts: n/a
Default Backfeed generator through dryer outlet?

In article ,
"Toller" wrote:

A couple years ago I asked the same question. Someone came up with at least
one example.
It does seem unlikely; if your main breaker is closed, your genny should
stall immediately when it tries to power the neighborhood. The only way you
could kill a lineman is if YOUR line if down and he is fixing it, or if (and
even this is a reach) you plugged in while he what handling a nearby line.
Of course, even then he is supposed to be protected from live wires by
insulation.


Bzzzzt, wrong answer and asumption, would you like to try for whgat is
behind Door #1.......

In your statement above, you make at least ONE very hugh assumtion that
is NOT correct. You assume that it takes many seconds, or minuets, of
backfeed power to electrocute someone downline. This is patently a
FALSE Assumtion. With the Transformers on the poles any amount of power
that gets put on the line generates an extremely Highvoltage Spike,
upline. It doesn't take, but a few miliseconds, of this spike to fry any
grounded entitiy across the HV side of the line. To protect linemen from
such spikes, they employ Grounding Straps on BOTH SIDES of the work area,
that in theory should protect them from such spikes. If the straps are
not installed correctly or if the workers are installing the straps
without using HotSticks, then they can certainly be ZAPPED by such
spikes, or power backfeed into the system. If you don't believe this
is true, just go ask any Lineman, and be prepared to get an earfull....

Me
  #27   Report Post  
Me
 
Posts: n/a
Default Backfeed generator through dryer outlet?

In article t,
Steve Kraus wrote:

It does seem unlikely; if your main breaker is closed, your genny
should stall immediately when it tries to power the neighborhood.


I think unless you have some sort of huge generator the load presented by
the outside world will look to the generator as pretty much a short to
ground. It would really have to be a situation where the power outage
resulted in you and your immediate neighbors being islanded. Where I live
there are 10 houses on the same pole transformer and even if that were
isolated I doubt my 4.4 kW machine could pull that load. Maybe if it were
the middle of the night and everyone's fridge just happened to finish
cycling before the power went out and and and... I think the risk is
nearly zip. But for safety to your machine more so than risk to any
lineman it might not be a bad idea to attach a reminder sign to your double
male cable or adaptor or whatever you do this with: TURN OFF MAIN BREAKER
BEFORE USING


Your thinking is just plain wrong.....


Me
  #29   Report Post  
Me
 
Posts: n/a
Default Backfeed generator through dryer outlet?

In article ,
"Pete C." wrote:

You are partially mistaken. Some older 240v outlets indeed do not have a
neutral connection, however newer ones do (code change). Since the
ground and neutral are required by code to be bonded at the service
entrance panel you will get the same functionality even if you're
feeding an older dryer outlet with no dedicated neutral i.e. using the
ground as a neutral.

The ground on the circuit may be a gauge lighter wire than the main
conductors which would limit your circuit capacity if you had a large
generator (~7kw or larger), but most people doing a dryer outlet
backfeed will have 5kw or smaller generators in which case even a
reduced gauge ground on a dryer outlet has adequate capacity.

Additionally since not only are the ground and neutral requited by code
to be bonded at the service entrance panel, there is also a required
ground rod (or two) connection at the service entrance panel which makes
it all but impossible to backfeed any power down the line if the main
breaker is off. The additional grounding of the utility system neutral
every few poles provides yet another level of protection.

The true risks are 1. Forgetting to shut off the main breaker, and 2.
Forgetting the danger of the double-male "suicide" cord and proper
connection / disconnection sequences.

Pete C.


There is one very hugh assumption being made here in this thread.
It seems that everyone ASSUMES that all the houses that are going
to be backfeed, have wiring that is in TOTAL Compliance with the NEC,
and that if it was once in compliance, it is still in compliance, many
years later. Just what happens when the Ground Rod connection corrodes?
When was the last time you checked yours? What about the Neutral/Ground
bonding strap? what is the resistance across that today, in your house?
Do you even know? Seems like very big assumptions to "Me"....

Me
  #30   Report Post  
Stormin Mormon
 
Posts: n/a
Default Backfeed generator through dryer outlet?

Oh, gee. Don't get started askign for specifics. Usenet is for wild ass
statements completely lackig in truth.

Since you asked, Myrtle Bingle was using her suicide cord in a power cut in
Arkansas in 1956. She neglected to turn off the mains, and killed David
Petersen, who was working on the line outside her house.

Myrtle was a darky, and she was promptly arrested and tried. Spent the rest
of her life in prison. Died last year.

Remember, now, this is Usenet. You can't believe everything you read.
--

Christopher A. Young
Do good work.
It's longer in the short run
but shorter in the long run.
..
..


wrote in message
...
Toller wrote:

I've done it. Lots of other people have also. But there actually have

been
fatalities as a result of doing it.


I've heard that's never actually happened. Can you name one?

Nick




  #31   Report Post  
Stormin Mormon
 
Posts: n/a
Default Backfeed generator through dryer outlet?

I was working on a trailer with a friend of mine. He want and "turned off
the mains" and then we found a couple sockets hot.

Turns out, he'd turned off the breaker for the dryer, thinking it was the
mains. I turned off the rest of the breakers.

How easy it is to make mistakes like that....

--

Christopher A. Young
Do good work.
It's longer in the short run
but shorter in the long run.
..
..


wrote in message
ups.com...
I'm surprised nobody's mentioned being sure to have (2) hot leads and
neutral, so you can power 117v circuits.

I've done this sort of thing many times over the years, but via single
117v 15a or 20a branch circuit. Main opened first, ditto all breakers
(which are accurately labelled as to which load). Of course circuit is
chosen so as to power selected "phase" which luckily has covered the
necessary loads. Then one breaker at a time on, and maybe rotated as
necessary. (Refrigerator does not need power 100% of time, nor does
furnace blower. Yada, yada.)

At a friend's house, opening main breaker one time, caused it to fail
to close forever more. Which sped up replacement.

HTH,
J


  #32   Report Post  
Solar Flare
 
Posts: n/a
Default Backfeed generator through dryer outlet?

How would any lineman know? If they have been "zapped" by this high voltage
spike you speak of, they wouldn't be telling you about it usually.

If they are putting grounds on a line with their bare hands it won't take a wild
generator to kill them.

"Me" wrote in message
...
In article ,
"Toller" wrote:

A couple years ago I asked the same question. Someone came up with at least
one example.
It does seem unlikely; if your main breaker is closed, your genny should
stall immediately when it tries to power the neighborhood. The only way you
could kill a lineman is if YOUR line if down and he is fixing it, or if (and
even this is a reach) you plugged in while he what handling a nearby line.
Of course, even then he is supposed to be protected from live wires by
insulation.


Bzzzzt, wrong answer and asumption, would you like to try for whgat is
behind Door #1.......

In your statement above, you make at least ONE very hugh assumtion that
is NOT correct. You assume that it takes many seconds, or minuets, of
backfeed power to electrocute someone downline. This is patently a
FALSE Assumtion. With the Transformers on the poles any amount of power
that gets put on the line generates an extremely Highvoltage Spike,
upline. It doesn't take, but a few miliseconds, of this spike to fry any
grounded entitiy across the HV side of the line. To protect linemen from
such spikes, they employ Grounding Straps on BOTH SIDES of the work area,
that in theory should protect them from such spikes. If the straps are
not installed correctly or if the workers are installing the straps
without using HotSticks, then they can certainly be ZAPPED by such
spikes, or power backfeed into the system. If you don't believe this
is true, just go ask any Lineman, and be prepared to get an earfull....

Me



  #33   Report Post  
Toller
 
Posts: n/a
Default Backfeed generator through dryer outlet?


"Me" wrote in message
...
In article ,
"Toller" wrote:

A couple years ago I asked the same question. Someone came up with at
least
one example.
It does seem unlikely; if your main breaker is closed, your genny should
stall immediately when it tries to power the neighborhood. The only way
you
could kill a lineman is if YOUR line if down and he is fixing it, or if
(and
even this is a reach) you plugged in while he what handling a nearby
line.
Of course, even then he is supposed to be protected from live wires by
insulation.


Bzzzzt, wrong answer and asumption, would you like to try for whgat is
behind Door #1.......

Bull. In the last 5 years we have had 3 poweroutages where I used my
generator. There wasn't a lineman within 5 miles of me on any of them. My
2kw generator is going to power up 80 square miles? Don't think so.


  #34   Report Post  
Steve Kraus
 
Posts: n/a
Default Backfeed generator through dryer outlet?

Me wrote:

Your thinking is just plain wrong.....


No, I think I'm on solid ground when I say that a load measuring in many
megaWatts, maybe hundreds of megaWatts depending on the area of the power
outage that I am downstream of, is essentially the same as shorting the
generator output to ground.

  #35   Report Post  
Pete C.
 
Posts: n/a
Default Backfeed generator through dryer outlet?

Me wrote:

In article ,
"Pete C." wrote:

You are partially mistaken. Some older 240v outlets indeed do not have a
neutral connection, however newer ones do (code change). Since the
ground and neutral are required by code to be bonded at the service
entrance panel you will get the same functionality even if you're
feeding an older dryer outlet with no dedicated neutral i.e. using the
ground as a neutral.

The ground on the circuit may be a gauge lighter wire than the main
conductors which would limit your circuit capacity if you had a large
generator (~7kw or larger), but most people doing a dryer outlet
backfeed will have 5kw or smaller generators in which case even a
reduced gauge ground on a dryer outlet has adequate capacity.

Additionally since not only are the ground and neutral requited by code
to be bonded at the service entrance panel, there is also a required
ground rod (or two) connection at the service entrance panel which makes
it all but impossible to backfeed any power down the line if the main
breaker is off. The additional grounding of the utility system neutral
every few poles provides yet another level of protection.

The true risks are 1. Forgetting to shut off the main breaker, and 2.
Forgetting the danger of the double-male "suicide" cord and proper
connection / disconnection sequences.

Pete C.


There is one very hugh assumption being made here in this thread.
It seems that everyone ASSUMES that all the houses that are going
to be backfeed, have wiring that is in TOTAL Compliance with the NEC,
and that if it was once in compliance, it is still in compliance, many
years later. Just what happens when the Ground Rod connection corrodes?
When was the last time you checked yours? What about the Neutral/Ground
bonding strap? what is the resistance across that today, in your house?
Do you even know? Seems like very big assumptions to "Me"....

Me


I didn't assume anything, I noted the code requirements which mean that
there would have to be a significant number of violations/failures for
there to be a safety issue past the obvious forgetting to shutoff the
main or the suicide cord which I noted as well.

Remember that even if your ground rod is rust, you've still got a ground
within a couple utility poles unless it is your actual service drop that
is down. It is all but impossible to build any dangerous voltage
relative to ground on the neutral. Even forgetting to pull the main has
a 99.999% probability of killing any small generator or tripping it's
circuit breakers before any dangerous voltage could build on the utility
mains.

Additionally the utility crews are supposed to 1. wear their insulating
gloves, 2. check lines for voltage before handling, and 3. ground lines
before working on them. All of which puts the odds of killing a utility
worker with your temporary generator connection worse than the odds of
winning Powerball. The chances of killing yourself with the suicide cord
on the other hand are much better.

Pete C.


  #36   Report Post  
Me
 
Posts: n/a
Default Backfeed generator through dryer outlet?

In article ,
"Toller" wrote:

Bull. In the last 5 years we have had 3 poweroutages where I used my
generator. There wasn't a lineman within 5 miles of me on any of them. My
2kw generator is going to power up 80 square miles? Don't think so.


Well it is easy to see that you "Don't think" period. Just what do you
think happens when your genset tries to energize a segment of the grid
by backfeeding thru the PolePig out on your pole? Does that one or two
second pulse before you little gensets goes up in smoke, show up on the
primary side of the PolePig? At what voltage does that impluse show
up at?. How far does that pulse go, before it dies of IR losses?
When you complete your 100 level College Course on Power & Transmission
come back and tell us all about it. Untill then, don't spread your
intelligence around to deeply cause your not fertilizing any crops.....

Me
  #37   Report Post  
Me
 
Posts: n/a
Default Backfeed generator through dryer outlet?

In article ,
"Solar Flare" wrote:

How would any lineman know? If they have been "zapped" by this high voltage
spike you speak of, they wouldn't be telling you about it usually.

If they are putting grounds on a line with their bare hands it won't take a
wild
generator to kill them.

"Me" wrote in message
...


They wouldn't have need to tell "Me", as I have been there, and seen
that, many times, in one of my previous lives. Have you ever really
looked at the Grounding Straps used by the Pro's? Have you ever noticed
that they have builtin devices that show if they go "Hot" while
connected? Where did the "Bare Hands" come from? All the linemen, I
have ever known work with UL Approved Insulated Gloves, and HotSticks,
but that doesn't mean they never get zapped or tingled on occasion.

Me
  #38   Report Post  
Pete C.
 
Posts: n/a
Default Backfeed generator through dryer outlet?

Me wrote:

In article ,
"Toller" wrote:

Bull. In the last 5 years we have had 3 poweroutages where I used my
generator. There wasn't a lineman within 5 miles of me on any of them. My
2kw generator is going to power up 80 square miles? Don't think so.


Well it is easy to see that you "Don't think" period. Just what do you
think happens when your genset tries to energize a segment of the grid
by backfeeding thru the PolePig out on your pole? Does that one or two
second pulse before you little gensets goes up in smoke, show up on the
primary side of the PolePig? At what voltage does that impluse show
up at?. How far does that pulse go, before it dies of IR losses?
When you complete your 100 level College Course on Power & Transmission
come back and tell us all about it. Untill then, don't spread your
intelligence around to deeply cause your not fertilizing any crops.....

Me


Care to tell me which brand of consumer level generator (~5kw) can
sustain a "one or two second" pulse into a megawatt level load? This
class of generator does not have a separate exciter to provide field
power under short circuit conditions. The field would collapse in
milliseconds or less if the generator was hot when it was connected, or
if an attempt was made to start the generator while connected, the field
would never develop in the first place.

Pete C.
  #39   Report Post  
Spud
 
Posts: n/a
Default Backfeed generator through dryer outlet?


"Steve Kraus" wrote in message
nk.net...
Me wrote:

Your thinking is just plain wrong.....


No, I think I'm on solid ground when I say that a load measuring in many
megaWatts, maybe hundreds of megaWatts depending on the area of the power
outage that I am downstream of, is essentially the same as shorting the
generator output to ground.


What about the downed power line your neighbors, and you.

http://www.google.com/
In the aftermath of a disaster there are circumstances that circumvent
conventional safety procedures. The utility companies rely heavily on
independent construction firms to quickly restore utility lines. Private
contractor employees are sometimes less familiars with the territory and the
established utility company procedures. On top of everything else there is
the stress caused by working long hours in inclement conditions and the
pressure to restore power to thousands of customers some of whom are in dire
need.



A line crew was dispatched at night to restore power to a small restaurant
in a mountainous area. The restaurant was served by a 3-phase, 12.47-kV,
tapline, three spans in length. "The crew found that tree limbs had fallen
into a corner pole (one span from the restaurant) short-circuiting the line
and blowing the fuses back at the tap pole. They also discovered that the
restaurant was using a generator to maintain service."

The foreman confirmed that the main breaker at the restaurant was open,
isolating the utility service. The crew tested and grounded the line a the
tap pole and began repairs. When one lineman climbed the corner pole to
remove limbs, he discovered that the jumpers and connectors were damaged and
decided to replace them. "When he removed the jumpers, he was positioned in
such a way that he was in contact with the under grounded portion of the
line," continues Drew. For some reason, the restaurant owner was checking
the generator and inadvertently closed the main breaker, backing power
through the transformer bank and energizing the line up to the open jumpers.
The lineman received a severe shock and died.


8/29/2005
As the number of personal electric generators grows, so does the threat of
injury to utility workers and generator operators.

If you connect a generator to your electrical panel without isolating it, it
’s simply a disaster waiting to happen. A generator that’s connected to the
power system can result in power lines being energized to line voltage of
7,200 volts or higher, whether they’re on the ground or still in the air. If
your generator is not isolated from the Cullman EC distribution system, the
transformer at your location acts in reverse and can actually step-up the
normal household voltage of your generator to our system voltage. If your
generator has energized power lines that are on the ground, the energized
lines could prove to be a safety hazard to you, your family, and especially
the linemen working to restore power.

As a matter of fact, a utility worker who was repairing damage from
Hurricane Dennis was killed this past July in south Alabama because of an
improperly installed generator. It is up to you to ensure the safety


Alabama, July 14, 2005 - Sumter Electric Cooperative (SECO) officials report
that a South Carolina lineman helping to restore power in Alabama after the
damage caused by Hurricane Dennis was killed late Tuesday, reportedly by an
improperly installed customer generator.Alabama authorities are looking for
the person responsible and indicate that charges are pending

all electric connections must comply with the National Electrical Code.
You may be liable for damage to property or injury to people that may result
from an improperly installed or operation of an emergency generator.





  #40   Report Post  
Richard J Kinch
 
Posts: n/a
Default Backfeed generator through dryer outlet?

As dangerous as this is, is this even possible?

All I can say is that here in SE Florida since Hurricane Wilma this week,
with 6 million people out of power, with my neighborhood as a sample, there
must be about 1 million backfed generators hooked up and running. It is
not just commonplace; it is the norm.

One neighbor had a (gypsy) electrician install a 4-wire twist-lock socket
in his garage specifically for backfeeding through a suicide cord.

Just stand in the electrical aisle of Home Depot for 5 minutes. You will
see a steady stream of people buying wire and plugs and asking how to make
a backfeed connection.

The same thing happened on a slightly smaller but still massive scale last
year after Hurricanes Jeanne and Frances. I don't recall any reports of
utility workers or users being harmed by the practice. There were
certainly more people poisoned by carbon monoxide from generators than hurt
or killed by electrocution from backfeeding or other misuse.
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