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Backfeeding with a portable generator - REAL safety concerns???

Discussion in 'Electrical Engineering' started by Friday, Sep 6, 2004.

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  1. Friday

    Friday Guest

    Hi All!
    I haven't had time to visit the group much lately, but I'm still here,
    and still preparing for TEOTWAWKI...
    .... as well as more practical, short-term survival issues, like the
    all-too-frequent power outages here during blizzards and ice storms in
    recent years (global cooling?).

    I live in Northern NY State, where we seem to have a 2-6 day power
    outage at least once every year or two, usually during the coldest part
    of winter.

    I picked up a Generac, industrial generator, 5kw (sustained), powered
    by a 10hp Robin gasoline engine. I'm told it will run for 12-14 hours
    straight on one 5-gallon tank of gas and an oil change. I keep it in a
    shed about 10 feet from my house. Plenty of gas, oil, and stablizer on
    hand.

    The generator has four, breaker-backed outlets: two 110's and two
    220's, one a NEMA L6-30 amp, same as the clothes dryer recepticle I
    installed in my basement a few years back.

    My housed is heated with a boiler and baseboard radiators. Hot water
    and stove are courtesy of natural gas. In the past, I've heated the
    house with the stove-top (oven won't light without power to the
    sensor), and I _REALLY_ don't like the idea of an open flame in my
    kitchen for several days in a row, especially while sleeping.

    The cost of having a professional panel-box job done to meet code is
    _OUT_ of the question. I don't have the $$$ and I only need once every
    year or two -and only if the power is out for more than 5-6 hours.

    I've been reading extensively about backfeeding to the 220-volt
    recepticle and at least one person in every forum says "NEVER do it!
    You'll kill youself, and/or a lineman, blow up your generator, burn
    your house down, catch scabies, etc.!"

    But SERIOUSLY... as long as I don't forget to open the main breaker
    before hooking up to the generator and disconnecting the generator
    before closing the main breaker (and I WON'T forget), what are the real
    dangers to backfeeding???

    I've talked to a few people who've done this all their lives without
    incident. Any professionals out there who can tell me the truth
    without getting hysterical???

    Here's my plan...

    When the grid goes off:

    1) Build a 40' cord (10/3 Romex) with male NEMA L6-30s (maybe 50s) at
    each end.
    2) Throw (open) main
    3) Throw (open) all other breakers
    4) Fire up generator and let run for 5 minutes to stablize current
    5) Plug in cord, first to house recepticle, then to generator.
    6) Close 220 breaker on main box
    7) Close breaker to furnace circuit (circulation pump/thermostat),
    refrigerator, and circuits to flourescent lights in kitchen and bath
    8) Run an extension cord into the house from the 110 outlets on the
    generator to power individual appliances one or two at a time as needed
    (TV, computer, radio, etc. - NO Microwave)

    When the grid comes back up:

    1) Open 220 breaker
    2) Turn off generator
    3) unplug cords to generator at both ends
    4) Close main breaker

    I honestly don't see how I can feed power back into the grid by
    mistake, unless, like I said, I forget to open the main- which I WILL
    NOT do. I live alone, so there's no danger of anyone else F***ing
    things up.

    What is the REAL danger in doing this?
    * Overheating the panel???
    * Main breaker failure???? (But HOW????)

    Thanks for any REALISTIC advice.

    Cheers,
    :)
    Friday

    PS: Like I said, there's not enough $$$ for a professional installation.
    I suppose I could pull the meter, but that would probably p*ss off the
    power company.

    --
    #####################################
    "The people cannot be all, & always well informed. The part which is wrong will
    be discontented in proportion to the importance of the facts they misconceive.
    If they remain quiet under such misconceptions it is a lethargy, the forerunner
    of death to the public liberty. What country before ever existed a century & a
    half without a rebellion? & what country can preserve it's liberties if their
    rulers are not warned from time to time that their people preserve the spirit
    of resistance? Let them take arms... The tree of liberty must be refreshed from
    time to time with the blood of patriots & tyrants"
    -- Thomas Jefferson
    #####################################
     
  2. Friday

    Friday Guest


    PS: What about grounding? I believe OSHA regulations require the
    generator (manufacturers) to have its own grounding system (being
    grounded to the chasis inmost cases). So by backfeeding into the house
    system, what safety procedures should I take to ensure a proper/safe
    ground?

    TIA
    Friday

    --
    #####################################
    "The people cannot be all, & always well informed. The part which is wrong will
    be discontented in proportion to the importance of the facts they misconceive.
    If they remain quiet under such misconceptions it is a lethargy, the forerunner
    of death to the public liberty. What country before ever existed a century & a
    half without a rebellion? & what country can preserve it's liberties if their
    rulers are not warned from time to time that their people preserve the spirit
    of resistance? Let them take arms... The tree of liberty must be refreshed from
    time to time with the blood of patriots & tyrants"
    -- Thomas Jefferson
    #####################################
     
  3. daestrom

    daestrom Guest

    Well, given that you already know this is against code....

    Here are some items to double check.

    *Always* plug the 'suicide cord' into the load first before the generator
    (plug into dryer receptacle first). Otherwise, the exposed blades on the
    plug at that end will be 'hot' from the generator when you go to pick it up.

    If your cord includes a neutral, then you don't really need a separate 110
    cord. Just turn on 110 branch circuits one at a time and they will get
    powered from the neutral and one of the 'hot' leads in dryer circuit.

    Since the service panel neutral will be connected to grounding rod (if
    *that* part of your installation is code compliant), then that will probably
    be enough of a ground for you. Of course, if the neutral lead from
    generator to dryer rect or from dryer to service panel opens up, you may
    have some mismatched voltages on any 110 circuits.

    Of course, if you just run extension cords into home (110 & 220 versions)
    and unplug equipment from house wiring and plug into extension cords, you
    don't have any problems at all. Put suitable plug/recpt on your furnace and
    you can run that on an extension cord too. No code problem, little hazard
    at all.

    daestrom
    P.S. And why not microwave?
    P.P.S. *NOBODY* ever *intends* to forget to open the main. And yet.....
    (sh__ happens).
     
  4. Friday

    Friday Guest

    Thanks daestrom - good, practical tips.
    Yes, it is. It's a VERY old house (150+ years), but was rewired about
    20 years ago.
    What might cause that to happen?
    What would the consequences be?
    Of course

    I was considering that. But with only two 110 recepticles on the
    generator....
    (And it _WOULD_ be nice to be able to walk into a room and simply flip
    on the overheads).

    I don't know enough about the subject to make use of those 220 outlets.
    The only thing in the house that runs on 220 is the clothes dryer.
    Are there "converters" I could purchase to allow me to make use of
    those 220 recepticles(on the generator) as you suggested?
    One is a standard NEMA L6 and the other is a four-prong recepticle
    marked "120/240 - 20 amp".
    (I only have a 5kw generator (about 6250 surge). If the boiler pump AND
    refrigerator both kicked on while I was running the microwave...)
    Yes. Granted. But that only happens to stoopid people.
    Right?

    Thanks d;-
    PS are you a certified electrician?
    I ask, because what worries me most, is that According to an article I
    read on one power company Website: "Main breakers _CANNOT_ be trusted
    to create a clean break." Sounds like scare tactics, but... Is there
    anything to that? Could a surge "jump" across the main breaker when the
    grid comes back up????

    --
    #####################################
    "The people cannot be all, & always well informed. The part which is wrong will
    be discontented in proportion to the importance of the facts they misconceive.
    If they remain quiet under such misconceptions it is a lethargy, the forerunner
    of death to the public liberty. What country before ever existed a century & a
    half without a rebellion? & what country can preserve it's liberties if their
    rulers are not warned from time to time that their people preserve the spirit
    of resistance? Let them take arms... The tree of liberty must be refreshed from
    time to time with the blood of patriots & tyrants"
    -- Thomas Jefferson
    #####################################
     
  5. Gunner

    Gunner Guest

    That you, or someone WILL forget to open that breaker and kill
    someone. At which point the heavens will open and your life (and the
    wife and kids of the dead people) will be turned to shit, now and
    forever amen.

    Not to mention if the power comes on, and you happen to still be
    connected..the transformer on the pole explodes milliseconds after
    your genset turns into a small but lethal fireball.

    Go to Home Depot, etc and buy a transfer switch. They are commonly
    available now for less than $200. You can do it yourself if you are
    handy.

    Oh..and never check for gas leaks or the level in your fuel tank with
    a lit match. Based on your post..I had to add that, in order to save
    your life or the life of someone else, as it appears you dont think
    very far ahead. Shrug.

    Gunner

    "At the core of liberalism is the spoiled child -
    miserable, as all spoiled children are, unsatisfied,
    demanding, ill-disciplined, despotic and useless.
    Liberalism is a philosphy of sniveling brats." -- P.J. O'Rourke
     
  6. SAMMMMM

    SAMMMMM Guest

    i don't know about the power co. guys up there, but around here, if you
    can't show them a
    transfer switch in your lit house, you may be out of electricity for a
    loooonnnnggg
    time. they'll pull the meter for you. <G>
    and you'll fight like hell to get it back.
    if you think it's expensive to install a transfer switch, wait til they
    require a complete re-inspection
    of your electrical system, and nit-pick it to death.
    you'll wish you had gone to home depot and bought a small (60 amp) switch
    and had it wired in on your essential needs.
    no, i don't work for the power co. but i know some who do.
    i put mine in.
    good luck, sammmmm
     
  7. Neil

    Neil Guest

    Check out http://www.justgenerators.co.uk/pages/powertransfer.htm

    This gives you some data.


    Life in prison for manslaughter / negligent homicide if you get it
    wrong and the fact that you will have destroyed a life and probably a
    family.

    N
     
  8. Safety verses cost is always a factor. If 50,000 people did it your way how
    many do think would die?
    You might get by, or you might get someone killed. Is it worth the risk?
    If that somone is child of yours you might consider the value of installing
    a transfer switch using an insured, licensed, and bonded contractor.
     
  9. OSHA rules only apply to employee workplaces and do not apply to private
    homes.
     
  10. B J Conner

    B J Conner Guest

    Yer an idiot.
    What do you think supervisors do in an outage? They drive around look for
    damage and priortize work for line crews. When they see you house with the
    lights on they know that you have a generator. They may or may not know you
    have a transfer switch. They'll be back to check.
    As someone else noted you'll be in the dark for a while untill they wre
    convinced it's done right.
    If you do hurt of kill someone most power companies in concert with the
    union will prosecute you vigerously. If you don't go to jail you may be
    bankrupt. It's fair, if they can keep terminally stupid people so poor
    they can't afford a house or a generator they may save someone's life.
     
  11. Condor Chef

    Condor Chef Guest

    snip..
    Want a clean break? Pull the meter.


    CC
     
  12. ShoNuff

    ShoNuff Guest

    The BEST answer is to FIX the grid so it will NOT go off!
     
  13. Jimmie

    Jimmie Guest

    If you always do what you say you will do NO PROBLEM. Invaribly when there
    is a problem it is caused by someone who knew what they were doing, they had
    it all planned out, they just made a mistake and property or life was
    damaged. While you may be willing to take this risk should some poor linema
    working out in the cold have to unknowingly take it too.
     
  14. Rex Tincher

    Rex Tincher Guest

    <snip>

    1. Generator runs out of gas while you are out of the house. Lights
    go off.
    2. Your hard-drinking Uncle Ernie is visiting. He troubleshoots
    problem. "Hey, lookit this! The main breaker was off!" Flip!
    Nothing happens, and he passes out.
    3. You come home, refill generator, and start it.
    4. Utility lineman, working on the downed power line a mile away,
    gets fricasseed.

    In other words, you are setting a booby trap that can be set off by
    *anyone* who visits your house during a power outage. Maybe you won't
    forget, but can you guarantee that none of your friends, relatives, or
    neighbors will turn that breaker on?

    Remember that those linemen have relatives, and those relatives may
    have guns. If they don't, then plenty of people will cheerfully loan
    them guns.
     
  15. Paul

    Paul Guest

    That cord should not be called a "Suicide Cord" but, rather, a "Negligent
    Homicide Cord". I can't believe any self-respecting engineer, technician or
    electrician would even entertain this conversation.
    During a storm, utility linemen have enough to worry about without any
    idiots using that set up.
     
  16. Guest

    It (backfeeding power through the main) happens only to people
    who have set up a system that makes it possible. Some would
    call them "stoopid". Others might use stronger language.
     
  17. Tim Perry

    Tim Perry Guest

    breakers can and do go bad. usually they go intermittent or open.
    its hard to predict just what will happen each time power is restored,
    sometimes nothing bad happens. i think the greater worry would be that you
    might have taken a lightning hit through the panel.
    i spend a lot of time repairing industrial equipment after a storm as moved
    through. a lot of times the root cause is matter speculation. what i have
    is a melted gob of goop that used to be a component.
    surge suppressors (TVSS) help protect your stuff but as they are installed
    after the main breaker or fuses the "mains" have to survive the current hit.

    for what its worth, when i service equipment, after i turn off the breaker i
    touch all formerly "live" connections with a grounding stick. i do this
    every time i turn power off before putting my body in harms way.


    id like to add my voice to those that recommend you not proceed with the
    plan as you described.

    for some reason it puts me in mind of a church in my home town that was so
    poor that it ran an extension cord from the house next door to get
    electricity.
    when city building inspector became aware of it he of course made then
    remove it.
    the very next sunday the reverend opened his sermon in a loud booming voice
    with: "and the lord said let there be light... then the devil came and took
    it away"

    i think there may be a solution to your problem that can implemented within
    your budget and be relatively safe sane and legal.

    i think you have take a prudent first step by asking for opinions of people
    who appear to be knowledgeable.

    the nest step is to discuss the matter with the local electrical inspector.
    he may suggest a scheme you both can live with. he may even point you toward
    an election who has something used on hand that will work just fine. is
    your power company NIMO? just curious
     
  18. Kilowatt

    Kilowatt Guest

    Sounds like I would like to be half as smart as you think you are.
    Fucking jerk
     
  19. If anyone got killed due to an inadvertent back feed, it would only be
    because the lineman or other workman violated safety procedures. A
    workman must treat a conductor as live unless he has tested and then
    grounded it. I am a graduate electrical engineer, retired from the
    electric utility business, and formerly supervised line crews among
    other things.

    One of my crews worked on the restoration phase on Long Island after
    hurricane Gloria. Contrary to doctrine, the first priorities were to
    restore power to the motel they were staying in and then to the best
    restaurants. They did work horrific hours. I will never forget what
    one told me on their return - "Jesus John, there is no way I could eat
    another lobster." There was an incident where there was an accidental
    breaker closure that would have otherwise energized the line section
    on which they were working but they were protected by their grounds.

    Many utilities require that points of protection must have a "visible
    break" so neither enclosed circuit breakers nor transfer switches are
    considered safe for personnel protection purposes. I do believe that
    it is a code violation if the generator does not carry a fourth ground
    wire but who is worried about the code during an ice storm?


    Regards,

    John Phillips
     
  20. B J Conner

    B J Conner Guest

    You and Friday should get together. You might get one good brain between
    you.
     
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