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  1. #1
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    Default Older Home with 2 wires and no Ground

    How can you hook up a GFCI in a older home or is this possible sense there is no ground wire.? If you can can you help with steps to do so Thanks

    Crawl Space Creeper

  2. #2
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    Default Re: Older Home with 2 wires and no Ground

    The GFCI does not require a ground for it to work.

    The GFCI monitors the current flow in the 'hot' wire and the current in the 'neutral' wire, comparing the two currents to each other.

    If there is 5 amps in the hot wire and 5 amps in the neutral wire ... no problem as all the current is going through the circuit.

    However, if there is 5 amps in the hot wire and 4.995 amps in the neutral wire ... there is 0.005 amps NOT going through the circuit - which means that 0.005 amps COULD be going through you. The would mean that you were somehow conducting to ground, I.e., you become the path (the 'wire' so to speak) to ground.

    A ground is only needed when testing the GFCI remotely from the GFCI (such as with a GFCI tester).

    From your standpoint all you would do is install the receptacle by connecting the two circuit wires to the terminals on the receptacle.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  3. #3
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    Default Re: Older Home with 2 wires and no Ground

    Jerry, will this control all the outlet on that GFCI??????? Thanks for all your help you guys been great


  4. #4
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    Default Re: Older Home with 2 wires and no Ground

    Quote Originally Posted by Rose Hallman View Post
    Jerry, will this control all the outlet on that GFCI???????
    If the GFCI is the first receptacle and the others are connected to the "Load Side" terminals of the GFCI, the GFCI will protect the other receptacles connected to it.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  5. #5
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    Default Re: Older Home with 2 wires and no Ground

    All true. GFCI's installed on 2-wire systems should be labeled "No Equipment Ground". Ideally it would be embossed on the unit, but most GFCI's come with little labels that say it.


  6. #6
    Marshall Brown's Avatar
    Marshall Brown Guest

    Default Re: Older Home with 2 wires and no Ground

    From a safety standpoint the GFCI provides protection of the downstream outlets but it does make it difficult to verify those outlets are protected using a standard 3 light tester.


  7. #7
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    Default Re: Older Home with 2 wires and no Ground

    Quote Originally Posted by Marshall Brown View Post
    From a safety standpoint the GFCI provides protection of the downstream outlets but it does make it difficult to verify those outlets are protected using a standard 3 light tester.

    What is the best way to test the outlets in this case?


  8. #8
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    Default Re: Older Home with 2 wires and no Ground

    Quote Originally Posted by john f miller View Post
    What is the best way to test the outlets in this case?
    Trip it with the built-in test button. Then check other outlets for power with a voltage sniffer.

    John Kogel, RHI, BC HI Lic #47455
    www.allsafehome.ca

  9. #9
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    Default Re: Older Home with 2 wires and no Ground

    Quote Originally Posted by John Kogel View Post
    Trip it with the built-in test button. Then check other outlets for power with a voltage sniffer.

    Thanks, somedays my brain does not work. Common sense should have told to do that.


  10. #10
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    Default Re: Older Home with 2 wires and no Ground

    Quote Originally Posted by john f miller View Post
    What is the best way to test the outlets in this case?
    The best test of a GFCI is always the built in test button.

    A GFCI tester makes a good secondary tester and is good for determining that older GFCIs actually do as they are supposed to to: not reset reverse polarity, trip off its receptacle when the GFCI trips, among other issues. Newer GFCIs have built in safety measures so those issues do not happen.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  11. #11
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    Default Re: Older Home with 2 wires and no Ground

    Quote Originally Posted by Jerry Peck View Post
    The GFCI does not require a ground for it to work.

    The GFCI monitors the current flow in the 'hot' wire and the current in the 'neutral' wire, comparing the two currents to each other.

    If there is 5 amps in the hot wire and 5 amps in the neutral wire ... no problem as all the current is going through the circuit.

    However, if there is 5 amps in the hot wire and 4.995 amps in the neutral wire ... there is 0.005 amps NOT going through the circuit - which means that 0.005 amps COULD be going through you. The would mean that you were somehow conducting to ground, I.e., you become the path (the 'wire' so to speak) to ground.

    A ground is only needed when testing the GFCI remotely from the GFCI (such as with a GFCI tester).

    From your standpoint all you would do is install the receptacle by connecting the two circuit wires to the terminals on the receptacle.

    As Jerry said, while the GFCI has a ground terminal, the GFCI does not care if the ground is not present. Any difference between the phase (hot) and neutral, will trip the circuit.


  12. #12
    Marshall Brown's Avatar
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    Default Re: Older Home with 2 wires and no Ground

    Weird, yesterday in a 15 year old upscale lake home. We found 4 GFCI's that would not trip mechanically. Not unusual to occasionally find one but I have never had that many in weeks much less one house.


  13. #13
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    Default Re: Older Home with 2 wires and no Ground

    Quote Originally Posted by Marshall Brown View Post
    Weird, yesterday in a 15 year old upscale lake home. We found 4 GFCI's that would not trip mechanically. Not unusual to occasionally find one but I have never had that many in weeks much less one house.
    What do you mean by "would not trip mechanically"?

    The GFCI would trip but the GFCI receptacle would still have power?

    The GFCI would trip when remotely tested but the GFCI receptacle would still have power?

    Both indicate that the GFCI was wired with line/load reversed.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  14. #14
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    Default Re: Older Home with 2 wires and no Ground

    Quote Originally Posted by Marshall Brown View Post
    Weird, yesterday in a 15 year old upscale lake home.
    GFCI's sometimes work differently in upscale lake houses.

    ' correct a wise man and you gain a friend... correct a fool and he'll bloody your nose'.

  15. #15
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    Default Re: Older Home with 2 wires and no Ground

    Quote Originally Posted by Marshall Brown View Post
    Weird, yesterday in a 15 year old upscale lake home. We found 4 GFCI's that would not trip mechanically. Not unusual to occasionally find one but I have never had that many in weeks much less one house.
    I find multiple faulty GFCI's on occasion. While it is not my job to find the why or how, I assume it to be most likely due to a lightning strike or surge in the area.

    The beatings will continue until morale has improved. mgt.

  16. #16
    Marshall Brown's Avatar
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    Default Re: Older Home with 2 wires and no Ground

    When we pushed the test button on the outlet, nothing happened. The outlets were powered at the time ad appeared to be properly polarized.


  17. #17
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    Default Re: Older Home with 2 wires and no Ground

    Quote Originally Posted by Marshall Brown View Post
    When we pushed the test button on the outlet, nothing happened.
    Sounds like defective GFCIs.

    I just had an electrician replace a brand new GFCI receptacle which was defective - I pressed the test button and one light dimmed on my tester, electrician got his meter and the H-N voltage was 68 volts, reset, tripped and H-N voltage was 84 volts.

    Told electrician it was probably either a bad GFCI or a nail/screw in a wire - replaced GFCI and the replacement GFCI worked properly ... other new GFCI went into the trash so it would not get installed someplace else.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

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