# Simple and stupid wiring question...three prong outlet..where is ground? **URL:** \ **Category:** Factual Questions\ **Created:** [September 7, 2021, 11:37am UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226 "2021-09-07T11:37:07Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [September 9, 2021, 6:24pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/41 "2021-09-09T18:24:35Z")
Yes, knob and tube wiring: > **[Knob-and-tube wiring](https://en.wikipedia.org/wiki/Knob-and-tube_wiring)** > > Pages for logged out editors learn more > > Knob-and-tube wiring (sometimes abbreviated K&T) is an early standardized method of electrical wiring in buildings, in common use in North America from about 1880 to the 1930s. It consisted of single-insulated copper conductors run within wall or ceiling cavities, passing through joist and stud drill-holes via protective porcelain insulating tubes, and supported along their length on nailed-down porcelain knob insulators. Where conductors entered... When I bought my first house, my father and I took it out. They used a piece as a Christmas ornament for years. When my father died, I went to my mother’s house for Christmas, saw the ornament and started sobbing. Good memories of Dad. ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [September 9, 2021, 7:03pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/42 "2021-09-09T19:03:33Z")
I’ve worked on knob & tube wiring. Horrible stuff, I’m shocked it didn’t cause more fires. Stuff I worked on was nearly 70 years old, so no “insulation” left to speak of. I’m glad this job consisted of removing the old garbage and using modern (1990s) cable to replace it. Also helped remove the fuse box and wire up the brand new Square D breaker panel. * * * What did the Christmas ornament look like? Was it made from the copper or porcelain or some mix? ---
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [September 9, 2021, 7:16pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/43 "2021-09-09T19:16:37Z")
> [@What\_Exit](#): > > What did the Christmas ornament look like? Was it made from the copper or porcelain or some mix? A porcelain knob and a porcelain tube tied together with a ribbon. We threw about a hundred more of them away with the old man bitching and walking on the ceiling joists. ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [September 9, 2021, 7:18pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/44 "2021-09-09T19:18:29Z")
Sounds pretty cool. ---
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [September 9, 2021, 7:23pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/45 "2021-09-09T19:23:31Z")
Definitely. And we didn’t save them. My mother came over and picked them up to make an ornament because he and his father make the same improvements in the first house my father and my mother bought 25 years prior to that. ---
**Author:** ![Folacin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/folacin/32/3195_2.png) [@Folacin](https://boards.straightdope.com/u/Folacin)\ **Post date:** [September 9, 2021, 8:12pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/46 "2021-09-09T20:12:07Z")
> [@UltraVires](#): > > They used a piece as a Christmas ornament for years. When the local telephone company buried all of their phone lines (1973 or so), it was considered good sport to go out and take target practice at the insulators on the now dead telephone lines. In addition, my older brothers and their friends scaled some of the poles to retrieve various size insulators. Those were painted white and black and turned into a chess set. I read somewhere that at least some of those insulators could now be sold to collectors - another profit making opportunity lost, much like mom throwing out our baseball cards. ---
**Author:** ![Just\_Asking\_Questions](https://avatars.discourse-cdn.com/v4/letter/j/ba9def/32.png) [@Just\_Asking\_Questions](https://boards.straightdope.com/u/Just_Asking_Questions)\ **Post date:** [September 9, 2021, 8:28pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/47 "2021-09-09T20:28:32Z")
> [@UltraVires](#): > > Yes, knob and tube wiring: Probably was. The house was built about the turn of the century. That is, the 20th century. 🙂 And I don;t think it was built originally electrified. I’m pretty sure it didn’t have neutral fuses, though. > [@Folacin](#): > > When the local telephone company buried all of their phone lines (1973 or so), it was considered good sport to go out and take target practice at the insulators on the now dead telephone lines. We must have had no good luck. Instead of shooting them, we took them. I still have a box of them, nice green glass ones. ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [September 9, 2021, 8:39pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/48 "2021-09-09T20:39:25Z")
I see the glass and ceramic insulators fairly often but NJ electrified early. The town I’m in had some electricity in the late 1800s. That was primarily for the Trolley though. By 1920 the town had a lot of electricity and we’re not really close the NYC. ---
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [September 9, 2021, 8:51pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/49 "2021-09-09T20:51:48Z")
> [@Just\_Asking\_Questions](#): > > The house was built about the turn of the century. That is, the 20th century. 🙂 I do that a lot and the kid says, “What, 2000?” and then I get slightly mad at first but then laugh and pat him on the head and look on Amazon for a walking cane and a rocking chair. ---
**Author:** ![Just\_Asking\_Questions](https://avatars.discourse-cdn.com/v4/letter/j/ba9def/32.png) [@Just\_Asking\_Questions](https://boards.straightdope.com/u/Just_Asking_Questions)\ **Post date:** [September 9, 2021, 9:18pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/50 "2021-09-09T21:18:45Z")
> [@UltraVires](#): > > and look on Amazon for a walking cane and a rocking chair. I bought a lawn on Amazon, just so I could tell those kids to get off’n it. Internet purchasing - Living in the future is grand! ---
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [September 9, 2021, 9:27pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/51 "2021-09-09T21:27:11Z")
Yeah, I want to drag kids, orphans preferably, onto my lawn just to yell at them to get the hell off of it. Think Clint Eastwood in Gran Torino. That is who I will be in five years. If you ask my wife, she says I’m already that now. 🙂 ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [September 9, 2021, 9:46pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/52 "2021-09-09T21:46:36Z")
> [@UltraVires](#): > > I do that a lot and the kid says, “What, 2000?” and then I get slightly mad at first but then laugh and pat him on the head and look on Amazon for a walking cane and a rocking chair. Just wait until you (or the kids) start referring to the 80’s and 90’s as “the late 1900s”. ---
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [September 9, 2021, 9:56pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/53 "2021-09-09T21:56:08Z")
Yeah, yesterday I was 20. Do any of you other old bastards feel that way? ---
**Author:** ![Somethingwitty1](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/somethingwitty1/32/8899_2.png) [@Somethingwitty1](https://boards.straightdope.com/u/Somethingwitty1)\ **Post date:** [September 9, 2021, 11:55pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/54 "2021-09-09T23:55:50Z")
I am confused. are you all talking about the third plug on a standard outlet or the inner workings of the wiring? Most of my house is, if I believe the building inspector, probably grounded with the third plug on the bottom. My basement still has some 2 prong outlets. there are a few that are “upside down”. I was told this was a legal way to replace an ungrounded 2 prong outlet with a 3 prong outlet, negating the need for an adaptor. This may have been grandfathered in. I am thinking of replacing the remaining 2 prong outlets with GFCI outlets. They come with a sticker saying they aren’t grounded or something. Supposed to be kosher code wise. Any thoughts? ---
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [September 9, 2021, 11:57pm UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/55 "2021-09-09T23:57:46Z")
> [@Somethingwitty1](#): > > I am confused. are you all talking about the third plug on a standard outlet or the inner workings of the wiring? We agree on the inner workings. When it is placed in the box, does the fat ground plug go up or down? ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [September 10, 2021, 12:08am UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/56 "2021-09-10T00:08:53Z")
Let’s say there’s a box with only one hot and one neutral wire inside of it; there’s no ground wire. Assuming local code allows it, you can install a standard, three-prong (hot, neutral, ground) receptacle in the box _as long as_ it is GFCI-protected. And there are three ways it can be GFCI-protected: 1. The receptacle itself can be a GFCI receptacle. 2. The receptacle is downstream from a GFCI receptacle. 3. The circuit breaker for the circuit is a GFCI circuit breaker. In addition - and as you mentioned - an ungrounded, three-prong receptacle that is GFCI-protected must have a sticker on it that says, “No equipment ground.” ---
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [September 10, 2021, 12:10am UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/57 "2021-09-10T00:10:11Z")
> [@Somethingwitty1](#): > > I am thinking of replacing the remaining 2 prong outlets with GFCI outlets. They come with a sticker saying they aren’t grounded or something. Supposed to be kosher code wise. > > Any thoughts? They aren’t GFCI protected unless you have a breaker or something else upline protecting it (it could include that outlet) not grounded properly. Stated differently: You don’t get GFCI protection if that outlet doesn’t have a proper ground upline. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [September 10, 2021, 12:14am UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/58 "2021-09-10T00:14:33Z")
> [@UltraVires](#): > > You don’t get GFCI protection if that outlet doesn’t have a proper ground upline. Aer you saying the neutral must be tied to ground inside the breaker panel? If so, I agree. Other than that, there’s doesn’t need to be a “proper” ground upstream for a GFCI to work. ---
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [September 10, 2021, 12:15am UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/59 "2021-09-10T00:15:42Z")
If there is a ground fault upline, you don’t get the benefit of a GFCI. Am I wrong? ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [September 10, 2021, 12:16am UTC](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226/60 "2021-09-10T00:16:37Z")
A GFCI only protects itself and things downstream from ground faults. It doesn’t protect anything upstream. Is that what you were saying? If so, then I misinterpreted your comment. [Previous page](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226.md?page=2) [Next page](https://boards.straightdope.com/t/simple-and-stupid-wiring-question-three-prong-outlet-where-is-ground/950226.md?page=4)