Can I use EMT as a ground?

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Dgonza9

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I read that it was allowable to have up to 16 #12 wires in 3/4" EMT.

Yeah, good luck getting that done. I have 8 and it wasn't easy to pull those. I was going to run a separate ground wire. But now I'm wondering if I can use the metal conduit as the ground here. I don't know if I can pull another wire through.

Acceptable?
 
Personally I would always pull an equipment ground, and never rely on conduit it's only as good as the weakest link.
 
I read that it was allowable to have up to 16 #12 wires in 3/4" EMT.

Yeah, good luck getting that done. I have 8 and it wasn't easy to pull those. I was going to run a separate ground wire. But now I'm wondering if I can use the metal conduit as the ground here. I don't know if I can pull another wire through.

Acceptable?

Yes, But if you are Piping and pulling a new run size accordingly and pull a ground conductor.
“Sections 250.4(A) and (B)”General Requirements for Grounding
and Bonding” set forth in detail what must be accomplished by the grounding and
bonding of metal parts of the electrical system. The metal parts must form an
effective low-impedance path to ground in order to safely conduct any fault current
and facilitate the operation of overcurrent devices protecting the enclosed circuit
conductors.”
 
Personally I would always pull an equipment ground, and never rely on conduit it's only as good as the weakest link.

100% agree. Did an electrician properly install that run? Cheap insurance if not.
 
I read that it was allowable to have up to 16 #12 wires in 3/4" EMT.
Yeah, good luck getting that done. I have 8 and it wasn't easy to pull those...
You scare the hell out of me. You are on the short circuit of frying yourself into being a crispy critter.

IMHO you do not have a clue.

Sorry... I'm done and will not bother you anymore in any of your multi threads...

Please be very careful in what you choose to do. You are playing a very serious game of "You Bet Your Life".
 
Some receptacles are rated as self grounding but it is a good idea to use a ground wire to the box. I sometimes will use one wire as a pull wire to pull two wires in, it's easiest with wire lube.

Edit: It is also easier to have one person feed the wire in while another pulls.
 
Some receptacles are rated as self grounding but it is a good idea to use a ground wire to the box. I sometimes will use one wire as a pull wire to pull two wires in, it's easiest with wire lube.

That's what I would do! You really don't need to push a fish tape through there if its was that tough of a pull. Post a picture of the pipe run. How long how many bends ect.. I'll try and help.
 
You scare the hell out of me. You are on the short circuit of frying yourself into being a crispy critter.

IMHO you do not have a clue.

Sorry... I'm done and will not bother you anymore in any of your multi threads...

Please be very careful in what you choose to do. You are playing a very serious game of "You Bet Your Life".


Please stay off my threads, sir. I'm a high school english teacher trying to upgrade my brewery, not an electrician.

HERE'S where I got my information on how many wires are allowable in 3/4" conduit.

If I handed you a copy of Dante's Inferno and watched you teach it, I'm sure it'd be equally confusing. But in my line of work, we welcome questions and don't belittle others.

Again, please stay off my threads. The last one got deleted because you can't act like a decent human being.
 
So do I just run a wire from the ground screw on the receptacle to the metal box it's in? The conduit goes to my cp, which is grounded to the electrical panel ground bar.

I may run a wire if I can manage to pull it. Funny, I thought 3/4" was plenty of room for this.

For most conduit, that is acceptable. Properly installed metal conduit is an approved bonding method between enclosures. You did not mention what conduit you are using...

You should pull once (plan ahead). Adding a wire can be tough. If you pull them all out, attach the ground and pull them back in, you will be much happier and spend much less time and curses:)

EDIT...Soap/Lube is for big wire...it should not apply to breweries...JMO
 
That's what I would do! You really don't need to push a fish tape through there if its was that tough of a pull. Post a picture of the pipe run. How long how many bends ect.. I'll try and help.

It's metal conduit (EMT) and it does have 3 bends. Here are some pics:

Control panel
a08d1b4b.jpg


Conduit run to receptacles

47193ffe.jpg
 
For most conduit, that is acceptable. Properly installed metal conduit is an approved bonding method between enclosures. You did not mention what conduit you are using...

You should pull once (plan ahead). Adding a wire can be tough. If you pull them all out, attach the ground and pull them back in, you will be much happier and spend much less time and curses:)

EDIT...Soap is for big wire...it should not apply to breweries...JMO

It's EMT. I think I mentioned it in the first post.

Can you give me a primer on how you would I pull all 10 wires at one time? Do you just tie them in a bundle?

I'm willing to redo it if that's the best plan.
 
As long as the fittings are wrench tight it should be sufficiently grounded. How are the boxes connected together?
 
It's EMT. I think I mentioned it in the first post.

Can you give me a primer on how you would I pull all 10 wires at one time? Do you just tie them in a bundle?

I'm willing to redo it if that's the best plan.

10 would be the absolute max, and I would lube them to reduce friction and scraping. It's easiest to hook one wire to the pull string I'd fish tape and tape the rest(tightly) to the hooked wire. As for the ground its more than to code to use emt as a ground as long as the couplings nd connectors are tight. I'm an electrician with info not judgement(pj) so feel free to PM me with any ?s! I always like a challenge!:mug:
 
It's EMT. I think I mentioned it in the first post.

Can you give me a primer on how you would I pull all 10 wires at one time? Do you just tie them in a bundle?

I'm willing to redo it if that's the best plan.

I'm sorry. I guess I missed that.

You will need a pull wire/tape/rope of some sort in the conduit. If you plan to re-pull, attach your pull wire to the ones you pull out and pull it in as you pull the wires out. This all works best with a person on each end...

Once you have a solid pull wire/tape, attach the bundle of wire you want to pull in in as compact a package as you can manage. Tightly wrapped electrical tape 6-8 inches down the bundle is usually all it takes with maybe one wire looped through the pull wire/tape. Make the connection as compact as possible! Staggering wires can help keep the end small and get you around bends.

Lube does help if you have lots of bends or too small conduit. Murphy's Oil is what the old timers used if you have that in your cupboard. The most important part is keeping the wires in a nice bundle while feeding in. A big spaghetti mess takes up much more space...

Work smart....best wishes:mug:
 
DaleHair said:
As long as the fittings are wrench tight it should be sufficiently grounded. How are the boxes connected together?

I used box spacers.
 
To pull all your wires in at once in the field we call it a head but u pretty much loop one wire around the head on the fish tape fold it I've nice and tight and stagger each individual going away from the head making it as slim and tight as possible if u don't have a fish tape make the loop do the head is round and push it! U don't want any bulges just nice and tight
 
For Its worth in regards to using EMT for conduit, I had a situation at home where a fitting worked its way loose (I'm guessing vibrations from the washing machine) on some that was installed before we moved in. If there wasn't a ground pulled and something used at that receptacle short circuited the ground would not have been made. This is why I never rely on conduit of any kind to provide the sole path to ground.
 
That's a good point. So it's allowable, but not recommended. I'll pull a ground wire.

Thanks for all the advice.
 
For Its worth in regards to using EMT for conduit, I had a situation at home where a fitting worked its way loose (I'm guessing vibrations from the washing machine) on some that was installed before we moved in.

That's why I say if it is installed properly, If there is any vibration, flexible conduit is needed. A loose fitting it is bad, potentially dangerous, even if a ground wire is installed.
 
At least it's not bare wire wrapped around porcelain insulator or a screw in glass fuse......
Ahhhhh the good ole daze!
 
BeerguyNC61 said:
At least it's not bare wire wrapped around porcelain insulator or a screw in glass fuse......
Ahhhhh the good ole daze!

I run into knob and tube from time to time.
 
Dgonza9, Although that chart you showed and the NEC say that it's permissible to fit 16, 12 AWG wires in 3/4" EMT, another section of the NEC states that you can only have a 40% fill in that pipe. That's about 6, #12s. http://www.lanshack.com/DesigningConduitRuns.aspx
As has been said, you can use EMT as a ground, but I always run a ground wire anyway. I've seen runs of conduit rust away in the middle.
Were you pulling solid or stranded wire? Stranded is much easier to pull. You can use wire lube or Ivory liquid dish detergent to ease the pull. If you can use two 45s instead of a 90 that will also make pulling easier. You can use LBs (or LR/LL s) http://www.google.com/imgres?imgurl...efurl=http://www.amazon.com/Cantex-Industries . They allow you to get closer to your boxes.
The more couplings you use the more chances there are to have the "head" get stuck. Since you're right up there near Chicago land (where they use pipe for everything electrical...), you could probably give an electrician the measurements and have him (or her) bend the pipe for you for a couple of bucks. Too late now though.
The Divine Comedy was a good read, especially the liner notes (Penguin Publishing) that showed what Dante was referring to. I would've been lost without them. Good luck, Pete
 
Dgonza9, Although that chart you showed and the NEC say that it's permissible to fit 16, 12 AWG wires in 3/4" EMT, another section of the NEC states that you can only have a 40% fill in that pipe. That's about 6, #12s. http://www.lanshack.com/DesigningConduitRuns.aspx
As has been said, you can use EMT as a ground, but I always run a ground wire anyway. I've seen runs of conduit rust away in the middle.
Were you pulling solid or stranded wire? Stranded is much easier to pull. You can use wire lube or Ivory liquid dish detergent to ease the pull. If you can use two 45s instead of a 90 that will also make pulling easier. You can use LBs (or LR/LL s) http://www.google.com/imgres?imgurl...efurl=http://www.amazon.com/Cantex-Industries . They allow you to get closer to your boxes.
The more couplings you use the more chances there are to have the "head" get stuck. Since you're right up there near Chicago land (where they use pipe for everything electrical...), you could probably give an electrician the measurements and have him (or her) bend the pipe for you for a couple of bucks. Too late now though.
The Divine Comedy was a good read, especially the liner notes (Penguin Publishing) that showed what Dante was referring to. I would've been lost without them. Good luck, Pete


Hmmmmm... Whoever wrote that code book needs to learn about something called a "logical fallacy. I don't get the contradiction in the code book. Does it make sense somehow that I can't see or is it really a contradiction? Why would they tell you you can "fit" that many wires in the pipe, but then later say to only fill it 40%?

I have 10 wires in mine. 8 #12 and 2 #10 for neutral and ground. They are stranded. I just plugged my numbers into an iPhone app "Conduit Fill Calculator" based on NEC 2007 code. For 10 #12 wires it says 3/4" EMT. Not sure how that fits in with the information you provide, which seemed to be a different code "569."

Once I used the lube they pulled easy. From what I read in the NEC book, it said that beyond 9 wires you have to consider it to have only 70% ampacity. But that would still be fine for my application.



Congrats on reading "The Divine Comedy." Did you read all three books? And more importantly, congrats on enjoying it. My students are starting it now and many of them dig it. They argue endlessly about the concepts of justice and sin.
 
You have to look at the code book as a source of information as well as being a safety guideline. It gives you the size of the wire and the size of the conduit as information so that you can calculate how many wires will fit in accordance with the fill capacity. Some installations allow a larger fill capacity than others and sometimes you are putting different size wires in the same conduit so you need the sizing information to do your calculations.

You also don't need to count the neutral wires for the ampacity de-ration but you do need to count them for conduit fill.

16 #12 THHN conductors is 40% fill on a piece of 3/4 EMT
 
So the chart I had was correct. I also plugged in all the conductors and their sizes into the iPhone app I mentioned. It also states that 3/4" is acceptable and is based on 2007 NEC Codebook.

I'm finding it hard right now to pigtail the #10 wires to share the ground and neutral wires on each receptacle. They seem to want to come out of the pigtail cap. I need to get caps sized for 3 #10 wires. I mine are sized to hold only 2.
 
I like the red Ideal wire nuts myself. I know it's old school and makes for a more permanent installation but you could solder and tape the connections.
 
yjfun said:
I like the red Ideal wire nuts myself. I know it's old school and makes for a more permanent installation but you could solder and tape the connections.

No disrespect to you but Ideal can shove their product...at least the last time I considered it. I once opened a ceiling box with at least 50 connections...more than half of the nuts were laying on the back of the box cover. Must have been vibration...never a problem with Rangers.
 
No disrespect to you but Ideal can shove their product...at least the last time I considered it. I once opened a ceiling box with at least 50 connections...more than half of the nuts were laying on the back of the box cover. Must have been vibration...never a problem with Rangers.
That must have been one huge electrical box. Mounted in the ceiling?

I'm standing in awe at the prospect of that wiring layout...
 
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