Electrical Grounding Question

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suemarkp
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Re: Electrical Grounding Question

Post by suemarkp »

Bnjneer wrote: Tue Oct 19, 2021 5:46 pm So, is the article saying grounding of light switches wasn't required until 2011? From this link provided to the article, it seemed convoluted, that I didn't see that in there.
You can read the current and previous versions of the NEC by going to the NFPA website (https://www.nfpa.org/codes-and-standards/). The NEC if document NFPA 70. You need to register with the site and give them your email in order to use the free access viewer. The viewer is awful too. The 1996 code doesn't have a table of contents, so you start at the front or back and hit next or previous page until you get to where you want to go. The 1999 edition, you can click on switches in the table of contents and it takes you to article 380.

The requirement to ground switches (which is to provide provisions for grounding metal faceplates) was first required in 1999. In 1996 and prior, it was only required if metal faceplates were installed. The relevant article for switches was different in 1999 - article 380 instead of 404 in the later editions.

I can see electricians missing things the first year it was in the code, especially if Continuing Ed is not required to renew their license. But it had been in the code for 6 years before the 2005 edition, so they should have known. Conversely, it is easy to miss little additions to the code the first time they occur if you didn't look at all the change bars the year it happened. So if they had old electricians they were probably used to not grounding switches unless they were in a commercial setting where metal faceplates were more common.

Note that "a nonmetallic box with integral meas for grounding devices" means there is a metal rim in the box that touches the switch or receptacle mounting yoke and the ground screw in the box connects to this metal. You sometimes see this on round light fixture boxes, but I've never seen a plastic device box with that feature. The NEC is full of references to devices that do not exist (the manufacturers try to get things mandated or allowed to support things they have invented and want to sell).
Mark | Somewhere in WA State
jharkin
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Re: Electrical Grounding Question

Post by jharkin »

Bnjneer wrote: Tue Oct 19, 2021 5:46 pm Thank you for the responses, so far.

House construction was completed in 2015. 2005 NEC was to be used for construction by the City.

All rescepticles are grounded. None of the light switches are grounded. The did run grounding wire to each wall mounted light switch junction box, but they didn't connect the light switches to the ground wire present.
Regardless of the fact that it wasn't technically "required" for any competent electrician to run grounded NM-B romex to the box, install a light switch with a ground screw and just leave the ground wire hanging loose? :oops:

Bnjneer wrote: Tue Oct 19, 2021 5:46 pm This builder is well respected in this community and builds high end homes.
That doesn't matter. Most new builds are crap. High end homes are just slightly less crap with the same shoddy workmanship and materials covered up under higher end cosmetics.

I bet if you pull some receptacles they are all $0.20 builder grade and wired with snap in backstabs. Its legal... but its junk.


Every time I move, within the first year I make it a point to open every single switch and outlet cover and check the wiring. Any missing/loose grounds get fixed, backstabbed outlets get replaced with commercial grade and clamped connections. I also use a circuit tracer to verify the labeling on the breaker panel is correct. I also visually check every plumbing joint and HVAC system I can get to for sloppy work. I almost always find cringe worthy stuff even the inspector missed - from minor things like unsealed ducts to big stuff like forgetting to install the high limit aquastat on an indirect water heater. And this has been true both for renovated antiques and for new homes built in the last 30 years.
Silverado
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Re: Electrical Grounding Question

Post by Silverado »

jharkin wrote: Thu Oct 21, 2021 6:21 am
Bnjneer wrote: Tue Oct 19, 2021 5:46 pm Thank you for the responses, so far.

House construction was completed in 2015. 2005 NEC was to be used for construction by the City.

All rescepticles are grounded. None of the light switches are grounded. The did run grounding wire to each wall mounted light switch junction box, but they didn't connect the light switches to the ground wire present.
Regardless of the fact that it wasn't technically "required" for any competent electrician to run grounded NM-B romex to the box, install a light switch with a ground screw and just leave the ground wire hanging loose? :oops:

Bnjneer wrote: Tue Oct 19, 2021 5:46 pm This builder is well respected in this community and builds high end homes.
That doesn't matter. Most new builds are crap. High end homes are just slightly less crap with the same shoddy workmanship and materials covered up under higher end cosmetics.

I bet if you pull some receptacles they are all $0.20 builder grade and wired with snap in backstabs. Its legal... but its junk.


Every time I move, within the first year I make it a point to open every single switch and outlet cover and check the wiring. Any missing/loose grounds get fixed, backstabbed outlets get replaced with commercial grade and clamped connections. I also use a circuit tracer to verify the labeling on the breaker panel is correct. I also visually check every plumbing joint and HVAC system I can get to for sloppy work. I almost always find cringe worthy stuff even the inspector missed - from minor things like unsealed ducts to big stuff like forgetting to install the high limit aquastat on an indirect water heater. And this has been true both for renovated antiques and for new homes built in the last 30 years.
Yeah, I do the same (within my severely limited skills) and I feel good. But the thought of what is in the walls makes me shudder…
jharkin
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Re: Electrical Grounding Question

Post by jharkin »

Silverado wrote: Thu Oct 21, 2021 7:34 am
Yeah, I do the same (within my severely limited skills) and I feel good. But the thought of what is in the walls makes me shudder…
Tell me about it. Ive run into 3 and 4 gang switch boxes on 2 or 3 different circuits (NEVER trust the box is dead unless you test every wire). Sometimes the neutrals are crossed. Or the electrician obviously just added on to whatever circuit they could find and one breaker controls half a room on one floor and half another room in the basement on the opposite side of the house :confused Overstuffed boxes everywhere and in one house there was a hanging splice on the 50A electric oven circuit just dangling in a crawlspace.

ugh.
michaelingp
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Re: Electrical Grounding Question

Post by michaelingp »

jharkin wrote: Thu Oct 21, 2021 9:25 am
Tell me about it. Ive run into 3 and 4 gang switch boxes on 2 or 3 different circuits (NEVER trust the box is dead unless you test every wire). Sometimes the neutrals are crossed.
I'm learning so much from this thread! Who knew BH's were such good electricians! Is it against code to have wires from two circuits in one box? Or to have the neutrals connected?
jharkin
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Re: Electrical Grounding Question

Post by jharkin »

michaelingp wrote: Thu Oct 21, 2021 9:37 am
jharkin wrote: Thu Oct 21, 2021 9:25 am
Tell me about it. Ive run into 3 and 4 gang switch boxes on 2 or 3 different circuits (NEVER trust the box is dead unless you test every wire). Sometimes the neutrals are crossed.
I'm learning so much from this thread! Who knew BH's were such good electricians! Is it against code to have wires from two circuits in one box? Or to have the neutrals connected?
I'm not sure if its technically against code, but its definitely good practice to only have one source of input power in a box... so if you kill the breaker for one switch in the box you know the entire box is dead and safe to work on.
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Tubes
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Re: Electrical Grounding Question

Post by Tubes »

jharkin wrote: Thu Oct 21, 2021 10:16 am
michaelingp wrote: Thu Oct 21, 2021 9:37 am
jharkin wrote: Thu Oct 21, 2021 9:25 am
Tell me about it. Ive run into 3 and 4 gang switch boxes on 2 or 3 different circuits (NEVER trust the box is dead unless you test every wire). Sometimes the neutrals are crossed.
I'm learning so much from this thread! Who knew BH's were such good electricians! Is it against code to have wires from two circuits in one box? Or to have the neutrals connected?
I'm not sure if its technically against code, but its definitely good practice to only have one source of input power in a box... so if you kill the breaker for one switch in the box you know the entire box is dead and safe to work on.
Agree, not good practice to connect neutrals (or share them or cross them), especially with Romex where the neutral is carried anyway. You do see more shared neutrals in THNN pulled through conduit.

This brings up a point. When you open your neutral bundle, be extremely careful. You've opened up a potential shock hazard. You may have killed the circuit for the light you are working on, but the other circuit's neutral can "back feed" through your body once you open it. Say the other circuit has a light on. When you open the neutral, the light will go out making all circuits appear dead. That is, until YOU become the connection back to earth when you touch the neutral and some other grounded item.

I use both a non-contact tester, and my little old test light to check all neutrals for voltage when the bundle is open.
daheld
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Re: Electrical Grounding Question

Post by daheld »

This discussion reminds me of a situation I had that wound up not being a big deal or a safety issue, but on the surface looked like a massive problem.

A few years ago we had a contractor out to relocate a washer and dryer from the basement to the main level of our ranch home. They do plumbing and electric, so both trades were there working at the same time. While the plumbers were working away on their stuff, I was talking to the electrician who was running a dedicated circuit for the laundry. I had a question about our finished basement lighting; he was super friendly and totally willing to take a look. At that time the home had 4' fluorescents that were recessed into the space between the floor joists and had a plastic diffuser panel cut to the size of the hole. I removed a diffuser panel and began to ask some questions about LEDs and such, and he started to freak out. There was 12 gauge Romex running through a hole in the joist that had just been cut. Exposed wires just right next to the metal fluorescent light fixture. He grabs a pen tester and tests it--the tester goes crazy. He says "THIS IS HOT!". He starts pulling diffusers off, finds more exposed, cut Romex and they're all hot. He finally went to his truck to get a multimeter, individually tested them all and they weren't hot after all. It was just interference from nearby electric.

But it was sort of a similar deal. At some point, someone removed some wiring or ran a new circuit or something and just lopped off those Romex runs at the joists. It took me like 30 minutes to figure out where it went and it definitely was not in use, and only a few minutes to just pull the wire and discard it.

Do stuff right the first time.
jharkin
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Re: Electrical Grounding Question

Post by jharkin »

daheld wrote: Thu Oct 21, 2021 11:58 am
But it was sort of a similar deal. At some point, someone removed some wiring or ran a new circuit or something and just lopped off those Romex runs at the joists. It took me like 30 minutes to figure out where it went and it definitely was not in use, and only a few minutes to just pull the wire and discard it.

Do stuff right the first time.
Thats another one that gets me. One of the houses i lived in was built in the 18th century (fun but that's a whole other topic) and that house had been renovated and modified and had systems replaced so many times that it was practically a museum of electrical and plumbing evolution.

I found knob and tube, armored cable, early cloth jacketed ungrounded grounded romex and modern plastic jacketed romex. Lots of old circuits that where dead but hadn't been physically removed (including all the knob) and I spent a lot of time chasing down and removing it all. my wife thought I was a bit off removing stuff that was already disconnected but it made me feel a lot better and made the mess a lot easier to understand (for me and the next owner).

Sorry MODS for taking us so far off topic......
brianH
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Re: Electrical Grounding Question

Post by brianH »

jharkin wrote: Thu Oct 21, 2021 10:16 am
michaelingp wrote: Thu Oct 21, 2021 9:37 am
jharkin wrote: Thu Oct 21, 2021 9:25 am
Tell me about it. Ive run into 3 and 4 gang switch boxes on 2 or 3 different circuits (NEVER trust the box is dead unless you test every wire). Sometimes the neutrals are crossed.
I'm learning so much from this thread! Who knew BH's were such good electricians! Is it against code to have wires from two circuits in one box? Or to have the neutrals connected?
I'm not sure if its technically against code, but its definitely good practice to only have one source of input power in a box... so if you kill the breaker for one switch in the box you know the entire box is dead and safe to work on.
Code allows as many circuits in a box as you want, assuming you adhere to box fill (# of wires based on volume.) There's no issue with 2+ sources in a single box.

You cannot combine neutrals, however. They must remain separate.
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hand
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Re: Electrical Grounding Question

Post by hand »

At it's heart, this isn't (or shouldn't) be a code discussion and the average homeowner shouldn't have to worry about interpreting code.

Homeowner, when notified of a deficiency, should consider:

1) Reaching out to builder to raise the issue and in hopes of an easy resolution if one trusts the builder
2) Contacting the AHJ (Authority Having Jurisdiction) for a judgement that the work does not meet code (though may be difficult if AHJ has already signed off)
3) A formal and documented inspection by a licensed Electrician and presumably a claim against the contractor's bond
michaelingp
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Re: Electrical Grounding Question

Post by michaelingp »

brianH wrote: Thu Oct 21, 2021 12:59 pm Code allows as many circuits in a box as you want, assuming you adhere to box fill (# of wires based on volume.) There's no issue with 2+ sources in a single box.
Thanks. I should have known that. A while back we had our service entrance box moved, and to do it they used a bunch of good size square junction boxes to patch the circuits from the old to the new location. Each box had many circuits in it. The County inspector questioned the large number of boxes in one spot, but was fine when explained the purpose.
brianH
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Re: Electrical Grounding Question

Post by brianH »

michaelingp wrote: Thu Oct 21, 2021 2:23 pm
brianH wrote: Thu Oct 21, 2021 12:59 pm Code allows as many circuits in a box as you want, assuming you adhere to box fill (# of wires based on volume.) There's no issue with 2+ sources in a single box.
Thanks. I should have known that. A while back we had our service entrance box moved, and to do it they used a bunch of good size square junction boxes to patch the circuits from the old to the new location. Each box had many circuits in it. The County inspector questioned the large number of boxes in one spot, but was fine when explained the purpose.
It's always a good thing to keep in mind when working on a particular box that, even if you kill the breaker for the circuit you're concerned with, there may be another in the box that can zap you. The non-contact voltage testers are a must before rummaging around.
michaelingp
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Re: Electrical Grounding Question

Post by michaelingp »

brianH wrote: Thu Oct 21, 2021 12:59 pm You cannot combine neutrals, however. They must remain separate.
This confuses me. Isn't combining neutrals exactly what happens if you use, say, 14/3 cable to run two circuits?
brianH
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Re: Electrical Grounding Question

Post by brianH »

michaelingp wrote: Thu Oct 21, 2021 2:43 pm
brianH wrote: Thu Oct 21, 2021 12:59 pm You cannot combine neutrals, however. They must remain separate.
This confuses me. Isn't combining neutrals exactly what happens if you use, say, 14/3 cable to run two circuits?
Are you talking about a multi-wire branch circuit? Those are a special case where the 2 hots come off of a single double-pole breaker (it must be a double pole or connected to act like a double pole). In that case, both hots use the single neutral as the return path. This is ok for two reasons, 1) the current on the neutral is only ever the unbalanced current from the 2 hots and 2) a single breaker throw kills both circuits. These MWBCs are becoming rare with the requirements for AFCI/GFCI everywhere.

Sharing or combining neutrals for multiple circuits isn't allowed because it's a potential shock hazard and it can potentially lead to unbalanced current (overcurrent) flow. If two 20A circuits shared neutrals but one of the neutrals failed somewhere on its way to the panel, the other neutral would now be carrying the current (max of 20A+20A=40A) back to the panel. That would overload the wire and cause a fire. The breakers wouldn't trip, because to them, the 2 hots are only carrying 20A.
suemarkp
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Re: Electrical Grounding Question

Post by suemarkp »

It is also a problem on GFCI and many AFCI protected circuits, as those devices will trip if the neutral has some other return path (via a ground wire, or a separate circuit's neutral). Adding AFCI breakers to old houses can be a pain because of this. I just did it to my house and only have one circuit that is a problem (out of 20+ AFCI circuits).
Mark | Somewhere in WA State
michaelingp
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Re: Electrical Grounding Question

Post by michaelingp »

brianH wrote: Thu Oct 21, 2021 2:59 pm Are you talking about a multi-wire branch circuit? Those are a special case where the 2 hots come off of a single double-pole breaker (it must be a double pole or connected to act like a double pole). In that case, both hots use the single neutral as the return path. This is ok for two reasons, 1) the current on the neutral is only ever the unbalanced current from the 2 hots and 2) a single breaker throw kills both circuits. These MWBCs are becoming rare with the requirements for AFCI/GFCI everywhere.
Yes, MWBCs. Thanks for the clear explanation. I made the mistake of thinking that because my house was wired by "real" electricians, it must be correct, but I have several multi-wire branch circuits where the breaker handles are not tied. They are at least on adjacent breakers. I'm not even sure why the electricians did this, since the amount of wire saved was miniscule, but it was 1987 if that makes a difference.
suemarkp
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Re: Electrical Grounding Question

Post by suemarkp »

In 1987, multiwire branch circuits did not require a handle tie unless both of the hots were on the same yoke (e.g. a receptacle with the upper half on red and the lower half on black). I think it was maybe the 2011 code that required handle ties on all MWBCs.

These were done as a way to save a wire and to help balance loads. In the early 1970's copper got rather expensive which drove aluminum wiring and multiwire branch circuits (although the latter were done in the 60's and earlier too).
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Tubes
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Re: Electrical Grounding Question

Post by Tubes »

michaelingp wrote: Thu Oct 21, 2021 9:10 pm I made the mistake of thinking that because my house was wired by "real" electricians, it must be correct,
In 2004, a real electrician forgot to protect outdoor shed outlet wiring with a GFCI. Then a real county inspector missed the error.

It happens.
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kevinf
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Re: Electrical Grounding Question

Post by kevinf »

Move into a house built in the prior century and enjoy seeing single wire bare knob-and-tube transition in a junction box to 2-wire cloth insulation that then transitions in another junction to modern 14-2 wire that terminates in a 3-prong GFCI receptacle.
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ironman
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Re: Electrical Grounding Question

Post by ironman »

Wow, as a master electrician and electrical inspector, there is some accurate info and some blatantly wrong info mixed about in this thread. Be careful!

Moral of the story: hire a licensed and reputable electrician.
Silverado
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Re: Electrical Grounding Question

Post by Silverado »

ironman wrote: Fri Oct 22, 2021 12:22 pm Wow, as a master electrician and electrical inspector, there is some accurate info and some blatantly wrong info mixed about in this thread. Be careful!

Moral of the story: hire a licensed and reputable electrician.
Call out the blatantly wrong info, that way we can benefit. Or perhaps you are wrong and you will benefit. Either way, at least one person benefits.
killjoy2012
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Re: Electrical Grounding Question

Post by killjoy2012 »

Tubes wrote: Wed Oct 20, 2021 10:08 am
Bnjneer wrote: Wed Oct 20, 2021 9:40 am perhaps this will show the photograph of one of the boxes...

https://i.postimg.cc/qMk9Ff1n/Photo-1.jpg
Wow. Lazy electrician. I don't care about the code. The Right Thing To Do is to ground them. The switch has a ground so you are good to go (note: older switches don't have a ground connection). And most perplexing is the apparent timer switch which has the ground wire cut off. Nice - not really.

I'm surprised your electrician didn't bind and bond the grounds with more than a wire nut. Most do so using bare sleeves (crimp splice caps). The good news is since they didn't, this is extremely easy to fix because there is plenty of ground wire length to play with in order to add a pigtail for the switch. As for the timer switch, since that ground is cut off, it looks like you'll need a new one.
Exactly. Lots of things wrong in this picture. And a great/classic example of Builders taking shortcuts to "slam bam" these homes together as fast as possible.

- No splice cap on the grounds that are tied together.
- Ground wire cut off on the dimmer.
- Ground screw on switch ignored.
- Hots on the switch aren't looped around the screw heads, and one is in backwards. Surprised they didn't quickwire the switches given how poorly/quickly this was done.
- Couldn't spend 30 seconds to tape off the gang box before spraying paint?

Yikes. Luckily, all easily correctable. If it were me, I'd go buy a new dimmer and rewire box correctly. The bigger problem is that the entire house is probably wired in the same slipshod manner.
suemarkp
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Re: Electrical Grounding Question

Post by suemarkp »

killjoy2012 wrote: Wed Oct 27, 2021 6:12 pm Exactly. Lots of things wrong in this picture. And a great/classic example of Builders taking shortcuts to "slam bam" these homes together as fast as possible.
What is worse are previously owned homes where all kinds of DIY badness has been done. Grounds twisted with no pressure connector, over filled boxes, under sized wires, wires wrapped the wrong way around screws, 39 cent backwired receptacles, neutrals used as ground to fool you on an ungrounded to grounded receptacle upgrade...
killjoy2012 wrote: Wed Oct 27, 2021 6:12 pm - No splice cap on the grounds that are tied together.
There is a (red) wire nut. That is all the code requires. What do you mean by splice cap -- a crimp ring? I hate those because you have to cut things off when you want to change something which takes away wire length.
killjoy2012 wrote: Wed Oct 27, 2021 6:12 pm - Ground wire cut off on the dimmer.
Yes, no excuse for that.
killjoy2012 wrote: Wed Oct 27, 2021 6:12 pm - Ground screw on switch ignored.
Yes, code violation at the time, but not before 1999 code. The switch has a brass self grounding tab, but those do no good on most plastic boxes.
killjoy2012 wrote: Wed Oct 27, 2021 6:12 pm - Hots on the switch aren't looped around the screw heads, and one is in backwards. Surprised they didn't quickwire the switches given how poorly/quickly this was done.
Not required for this type as these look like "backwire" terminals. You can put two wires under each screw (one one either side of the screw head) and you don't loop it around the screw. You can also choose to wrap the wire around the screw if you wish. If you use the push in Quickwire holes, those are at least more suitable for low load devices like light fixtures than a receptacle that could have a space heater plugged into it.
killjoy2012 wrote: Wed Oct 27, 2021 6:12 pm - Couldn't spend 30 seconds to tape off the gang box before spraying paint?
Whose job is that during construction - the electricians or the sheetrock/texture guys or the painters? That's the contractor's fault, as he needs to coordinate and assign tasks between subs.
Mark | Somewhere in WA State
killjoy2012
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Re: Electrical Grounding Question

Post by killjoy2012 »

What NEC code requires is often a lower bar than how things should be done if you care about quality. Most home builders working on cookie cutter subs are overly focused on speed. As long as the inspection passes and the light turns on until the house is sold -- good enough to them. Others of us are more concerned about quality and that gets into the 'art' of being an electrician.
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