Why does this wire not have a ground?

Discussion in 'Electrical and Wiring' started by farmerjohn1324, Nov 30, 2017.

  1. Nov 30, 2017 #1

    farmerjohn1324

    farmerjohn1324

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    This cable went to a box that had a GFCI and a switch. It only has two wires, hot and neutral. It was a metal box and there was also a separate ground wire attached to the metal box (green) that I traced back to a receptacle that is on a different circuit.

    I want to reconnect this cable to a new GFCI, but will it work with no ground? Obviously not, but what do I hook the ground up to? This green ground was connected to the metal box, but my new box will be plastic. Can I hook up a ground wire to the GFCI outlet that is attached to another circuit? These outlets all previously worked.

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  2. Nov 30, 2017 #2

    nealtw

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  3. Nov 30, 2017 #3

    Sparky617

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    It is an older house without grounds. The Romex appears to be old cloth covered wire common in the early to mid 1950's and maybe a bit later. You can install a GFCI like this in a house without ground wires, it will function as a GFCI. I believe the cover plate should be marked to indicate that there isn't a ground.

    If you're doing a lot of remodeling, I'd update the wiring to include grounds.

    https://www.thisoldhouse.com/ideas/replacing-two-prong-receptacles

    Tip: Even if an outlet box isn't grounded, installing a GFCI in it will still protect you (and your tools and appliances) from ground faults. But an ungrounded GFCI can't safeguard sensitive electronics, such as a computer or phone, from the interference caused by stray currents. The National Electrical Code requires you to stick a label on the receptacle that reads, "No equipment ground." These labels come in the box with a new GFCI.

    http://www.ecmweb.com/content/replacing-2-wire-ungrounded-receptacles
     
  4. Nov 30, 2017 #4

    farmerjohn1324

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    When you say "the next box" do you mean the receptacle on the other circuit or you mean the next GFCI on this circuit. Because there will be 3 GFCI's in series, one of which I would have to assume will have a microwave on it.

    If the ground can't be attached to the recep on the separate circuit, then why has it been working this way for so long? In case of overflow, does it really matter what ground path the current takes back to the panel?
     
  5. Nov 30, 2017 #5

    Snoonyb

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    Is the ground conductor in the same romex that the switch leg is in?

    If it is you can measure between the hot conductor in the switch leg to grnd. and if you have 120V, the grnd. is active, and you can pigtail from the GFCI to the grnd. conductor.
     
  6. Nov 30, 2017 #6

    farmerjohn1324

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    Can it safeguard a microwave?

    It would be a lot of work to replace that one old Romex. Would need to remove entire wall panels or drywall from the ceiling.

    There will be 3 GFCI's on this circuit. I suppose all 3 will act as miniature breakers/fuses to prevent excess current. In this case, what is the point of grounding any circuit that is protected by GFCI's?

    What if a ground comes over from a receptacle on a different circuit? Doesn't that make sense because it would still have a path back to the ground bus bar on the panel? Apparently, that's how it's been hooked up for years.
     
  7. Nov 30, 2017 #7

    farmerjohn1324

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    No. The ground was a single, loose green wire that was wired from a receptacle on a different circuit.

    I know that is odd wiring, but it apparently worked for years. And it makes sense. As long as current can get back to the ground bar in the panel, why does it matter what path it takes?
     
  8. Nov 30, 2017 #8

    Snoonyb

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    "you can measure between the hot conductor in the switch leg to grnd. and if you have 120V, the grnd. is active, and you can pigtail from the GFCI to the grnd. conductor."
     
  9. Nov 30, 2017 #9

    nealtw

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    It is only a problem when something goes wrong. Just screwing the outlet into the box makes a connection so adding a ground to that box make no difference.

    Running a wire to the next box with a ground wire I think is against code.
    What can happen. If you have 2 wire with out ground, there is no guarantee that the ground in the next box runs back to the breaker, it may just be a short addition to an old circuit.
    If there is a short in one box that does not trip the breaker, the next box connected by ground now is live with 120 volts. If that other outlet is on the other leg you would have a potential of 240 volts at both boxes.
     
  10. Dec 1, 2017 #10

    Snoonyb

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    He's replacing a metal box, with a plastic box.
     
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  11. Dec 1, 2017 #11

    farmerjohn1324

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    You said if it's in the same Romex, which it's not.

    Also, since all of the outlets on this circuit are GFCI's, is it safe to not have a ground wire in the cable going to the first outlet in the series?
     
  12. Dec 1, 2017 #12

    nealtw

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    If you have the first outlet gfci protected and wired correctly they all will be protected with that one outlet.
     
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  13. Dec 1, 2017 #13

    Snoonyb

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    And it was purposely omitted from the quote, in response to your comment that it was a stand alone conductor.

    If you choose.

    In a kitchen I always connect a grnd. conductor

    As previously discussed, you only need a single GFCI to control all the recep. on the circuit, which are downstream of the GFCI, you power them from the load terminals of the 1st, in succession, which means that were there to be a fault in any one of them, they all shut off, downstream.

    However, if you want each individual GFCI powered separately, and individual from all the rest, you power them from the line terminals.
     
    Last edited: Dec 1, 2017
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  14. Dec 1, 2017 #14

    farmerjohn1324

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    Okay.

    Now if I were to reconnect the single green ground wire to the first GFCI in the series, would it be a hazard? Would it make any difference at all? Would it allow me not to have to put that sticker on the outlets?

    Because that would create a path for current to reach the ground bar on the panel (and eventually the Earth), right? The fact that it comes from a different circuit is irrelevant to it's ability to act as a ground wire.
     
  15. Dec 1, 2017 #15

    nealtw

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    That is against code in some places
     
  16. Dec 1, 2017 #16

    afjes_2016

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    Absolutely incorrect.
    GFCIs are not for this purpose and do not provide this type of protection at all.

    I would highly suggest farmerjohn that if you are going to be doing a lot of electrical work at your job that you take some time on your own and do some study work on the internet and learn some basics of how different devices work and function; such as a circuit breaker, GFCI, AFCI, fuse, grounding a receptacle or switch needs etc. It will save you a lot of other reading and confusing yourself in the long run. Learn the basic terminology; for without the proper terminology you will not be able to follow the proper logic needed in order to accomplish your task successfully and safely and may end up causing harm to someone in the future.
     
    Last edited: Dec 1, 2017
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  17. Dec 1, 2017 #17

    Snoonyb

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    Please site a code section applicable to the NEC as adopted and amended in the county in Florida the OP resides in.
     
  18. Dec 1, 2017 #18

    nealtw

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    I can not. But I will see if I can dig it up.
     
  19. Dec 3, 2017 #19

    farmerjohn1324

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    What is the proper way to bend/break the tabs on a work box? It is always extremely difficult for me to slide wires in and out of them. Am I supposed to break them off completely?
     
  20. Dec 3, 2017 #20

    Snoonyb

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    No! They are designed that way as a retainer so that the 6" of working conductor length, is not diminished.
     

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