Connect with us

Ground outdoor outlet?

Discussion in 'Electronic Basics' started by DaveC, Aug 23, 2003.

Scroll to continue with content
  1. DaveC

    DaveC Guest

    In an old home with ungrounded electrical system, my father wants to add an
    outlet on the outside of the house near the porch.

    Does the NEC require that this be grounded?

  2. Grounded and GFI.
  3. In short no. You have to do it right to meet code. There are some good
    reasons for the code. It tends to save lives and prevent fires.

    Consider this an opportunity to upgrade at least one circuit to current
    code with a real ground.
  4. Alain Beguin

    Alain Beguin Guest

    on 23/08/2003 in message
    This would be very dangerous, even a crime, because it could put high
    voltage on the conduit...
    Never, never do that! You would put your and others life in danger. :-(

    Best regards,
  5. DaveC
    No. But there might be another legitimate ground nearby. Is the location
    of the proposed outlet near any metal water pipes?
  6. Ralph Farr

    Ralph Farr Guest

    Hi Dave,
    The GFI outlet has to have a ground to work. I would highly recommend
    installing this type of outlet as it can save your life or someone elses
    in wet areas - also it is mostly likely required by your local elecrical
  7. Technically, no. But practically (and legally) yes.

    GFCIs work by detecting whether any current is going somewhere
    other than the return neutral wire. No ground reference is used,
    it is completely differential.
    No argument there.
  8. Guest

    It does???? I have often seen replies to similar questions here that
    specifically said that a ground was not required for the GFI outlet to
    function - and a GFI outlet could be used in a two wire system
  9. Gary Tait

    Gary Tait Guest

    The conduit would be more legitimate than a water pipe. Not saying it
    is okay to use a conduit. The proper way to do it would be to run a
    new 12/2 with ground to the panel.
  10. DaveC

    DaveC Guest

    What are my options to run just a ground back to the panel? If I understand
    the code correctly, a ground isn't considered a current carrier and can be
    run outside the house, even buried in the earth (I'm speaking of an insulated
    wire, of course).

  11. Kevin Ricks

    Kevin Ricks Guest

    The NEC [210-7 (d)] allows any 2 wire (2 prong) ungrounded outlet to be
    replaced with a GFCI (3 prong) as long as a label is placed on each outlet
    that says " GFCI protected / No equipment ground" (You will usually find
    these stick-on labels in the GFCI package). Any of the outlets in the house
    can be 'upgraded' to 3 prong by adding GFCI's. (Check for variations in
    local codes).
    A GFCI does NOT require a ground to function and does nothing with the
    ground other than just pass it through the receptacle. Also the GFCI does
    not create a ground so when adding additional outlets in this manner be sure
    that you do not connect anything to the ground screw(s), (unless it actually
    goes to ground). i.e. Do not connect the grounds on 2 new outlets together
    even though the new cable between them will have a ground wire. This would
    create an isolated ground situation which is much more dangerous than no
    ground at all.
  12. A GFCI receptacle does not need an equipment ground wire to work
    (third wire, almost always Bare or GREEN). In fact if there is no
    grounding wire do not add one to the box unless you take it back to
    the electrical panel.

    The GFCI looks at the current passing from hot to neutral. It there is
    a Difference more than 5 mA it trips. It works with or without an
    equipment grounding condictor attached to the green screw on the

    You can safely use a GFCI on a two wire circuit. You are supposed to
    however use the sticker that comes with it telling there is NO
    EQUIPMENT GROUND attached to the GFCI.

    In fact the only way legally you can replace a two wire receptacle
    with a 3 wire one, has equipment grounding capability, is to use a
    GFCI and the sticker " no equipment ground " on a two wire circuit.
    When replacing the receptacle you use the LINE terminals on the GFCI.
    The GFCI will also protect other outlets installed downstream from the
    GFCI. Those outlets are connected to the LOAD terminals of the GFCI.

    Make sure you read the installiation instruction that are supplied
    with the receptacal when installing it. Leviton includes a nice sheet
    of instructions.

    Gary K8IZ
    Washington State Resident
    Registered Linux User # 312991
  13. Ralph Farr

    Ralph Farr Guest

    Sorry about the incorrect information on the GFI needing a ground to
    function. Outdoor outlets are much safer if they are grounded as much
    equipment that is connected to these outlets normally uses the third
    ground conductor for your protection. It is possible that your existing
    outlets are grounded if the wires are run through metal conduit and the
    outlets mounted in metal outlet boxes. If not then you most certainly
    have no ground and the best solution would be to run a new wire back to
    the breaker box.
  14. Actually, a GFCI does NOT require a Ground to function. In fact, the ground
    hole of the GFCI is NOT connected to anything in the GFCI. For an inside
    outlet, installing a GFCI in an ungrounded system is accepted practice,
    provides shock protection, and will meet Code. I do not know off-hand what
    the rulse are for outdoor outlets.

    --- sam | Sci.Electronics.Repair FAQ Home Page:
    Repair | Main Table of Contents:
    +Lasers | Sam's Laser FAQ:
    | Mirror Site Info:

    Important: The email address in this message header may no longer work. To
    contact me, please use the Feedback Form at Thanks.
  15. jakdedert

    jakdedert Guest

    The NEC allows grounding to any verified ground source when retrofitting
    two-wire systems. That's not to say that it's a good idea, but it's better
    than nothing. Best to pull a wire back to the service ground. There's also
    a rule about the type of enclosure for outside outlets. They must be
    completely covered...even in use. The old style plug covers, which covered
    the outlet only when unused, are no longer acceptable. The new ones have a
    large shield or door which covers the entire shebang, with slots underneath
    to allow passage of cables.

    The old ones would allow water to wick up--or dribble into--the outlet
    itself when a cord was plugged in...only protected well when unused.

  16. Gary Tait

    Gary Tait Guest

    You pretty well have to follow the path of the original circuit as
    well as you can.
  17. Gary Tait
    That would be fine, but if you run anything back to the panel, you can
    just about as easily run the whole romex.

    Under normal circumstances a ground wire doesn't carry current, but it
    has to be prepared to do so in the event of say a short from the hot to
    the case of an appliance. If the case were grounded, then even if you
    were holding the case, you would be outside the circuit and unaffected.
    The ground wire bonded to the case would carry the errant current.

    If there were no corrosion problems, you *could* burry an uninsulated
    ground wire. The ground wire is supposed to be electrically connected to
    the real ground, and that is exactly what a ground electrode does.

    And a metal water pipe does make a good ground. There are certain
    considerations: it should also be bonded to the neutral bus on the main
    service panel; there shouldn't be any non-metal fittings between your
    connection and the pipe entrance to the house; and there should be a
    jumper around the water meter. In other words, it should be electrically
    continuous to the ground.

    NEC compliance is somewhat different than electrical and practical
    reality. I understand NEC 2002 didn't allow water pipes a supplemental
    ground connection.

    This may confuse more that elucidate, but the issue is discussed here

    But, of course, you didn't say a water pipe was available.
  18. DaveC

    DaveC Guest

    No worries, Mate!
    It turns out that the rooms where I was adding the outdoor outlet did have a
    3-wire circuit. This extension of the house is newer than the original house,
    which has only 2-wire circuits.

    So, the ground issue is a non-issue.

    But I learned much about GFCI and grounding requirements thanks to all who
    contributed here.

    Dave C
  19. Sure you can. But you can save some trouble by just hooking the hot wire
    to a metal plate and marking it "Palm Here".
  20. actually most all outdoor outlets have to be GFCI according to the
    NEC. I seem to remember a couple of exceptions when there is no access
    to an outlet, like a single outlet an appliance like a freezer is
    plugged into in the garage, though not technically out doors still
    closer to ground than most outlets indoors.

    Now when you upgrade an outdoor piece of equipment like an air
    conditioner, the ground mounted version you are required to provide a
    service outlet within 25 feet of it and it needs to be GFCI. That is
    true for those roof mounted air conditioners also.

    The real point was the GFCI does not need the equipment grounding wire
    to be safe as it does not use that wire.

    All interesting stuff.

    Gary K8IZ
    Washington State Resident
    Registered Linux User # 312991
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day