DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   Electrical (http://www.diychatroom.com/f18/)
-   -   Grounding conduit instead of using a ground wire? (http://www.diychatroom.com/f18/grounding-conduit-instead-using-ground-wire-24600/)

stringtheories 08-01-2008 08:06 PM

Grounding conduit instead of using a ground wire?
 
Ok, this is my first post, so hello and good evening to everyone and thanx for any help/advice you can offer me. I apoligize if this question has been asked elsewhere on the forum, but i did browse through as much of it as i could before i decided to post-if i missed it let me know.

Ok, so my question is : when rewiring an old house, is it acceptable or even plausible to ground everything to the conduit and romex(its all metal) or should someone just put a seperate groundwire in while they are at it? Is this kind of grounding safe or even up to current NEC code?

Also, if someone is doing it this way do they have to connect a grounding wire from the conduit to the ground on the outlet or would it already just be ground through the casing?

As some of you may suspect, yes, someone is doing this currently to my parents house-my uncle- and the way he is wiring things seems a bit illogical to me when i look at how the outlets are suppose to look when wired as per the diagram on the outlet box, compared to how it actually looks. And I like to give people the benifit of the doubt, but while i was over at there house the other day i notice the outlet he was using for his power tools(from an extension cord) did have a wire attatched to where the ground is suppose to be attatched, but no other outlets are set up like this, and when I was over there today there was no wire on that outlets ground terminal either. Why would he have put it on to take it off? and why only that outlet? it all just makes me suspicious:eek:...so again, any advice you could offer would be greatly appreciated. :thumbup:

chris75 08-01-2008 08:18 PM

Metallic raceways are allowed to be used as the equipment grounding conductor.


But, IMO, if I personally didnt install the conduit, it would be getting a seperate equipment ground, only because you never know the condition of the existing pipeline.

theatretch85 08-01-2008 08:55 PM

When I install conduit (especially long runs) I always run a ground wire, at least a 14 gauge wire. I wired up an small tool shop once with a few circuits along the wall for various tools and ran a separate ground wire for each circuit down the same run of conduit, probably a bit overkill but oh well. I tend to make sure that all the conduit connections are good and tight and wont be coming loose any time soon, so I would probably be ok with just using the conduit as a ground, but I like the peace of mind that if the conduit ever broke down at any point there would still be a solid ground. Honestly I don't know what would cause a conduit run to breakdown unless of course there was physical damage done to it (but then I am sure you would have to worry about the conductors inside it being damaged as well).

Speedy Petey 08-01-2008 09:05 PM

Quote:

Originally Posted by stringtheories (Post 145034)
Ok, so my question is : when rewiring an old house, is it acceptable or even plausible to ground everything to the conduit and romex(its all metal) or should someone just put a seperate groundwire in while they are at it? Is this kind of grounding safe or even up to current NEC code?

Please explain this. Is the installer running NM cable in the conduit???

I agree with Chris, with metallic conduit a ground wire is not mandatory, but I ALWAYS run one.

stringtheories 08-01-2008 09:44 PM

i have no idea what NM cable is, maybe i got my terminology wrong when using the word romex? He is using metal conduit that is solid, and then also the type i am not sure what it is called, that is flexible, but still metal. As far as the wires, he says he is using BX? I do know that it is 12 gauge-not sure if that matters.

I know very little about wiring, but I understand the importance of a good ground(I saw people get shocked from faulty wiring before), and i do not trust this guy to properly connect all of the conduit together. Hes doing things like running conduit through holes hes punching in ductwork to get it through to places he wants it to be, and up the corner of closets and stuff like that. The worse part is that my parents have asked him to run a ground wire, but he refuses to run it, and says they have nothing to worry about(this being before he was very far along in the project).

Thanx for the responses everybody. I guess this is just a perfect example of why not to hire family...

Speedy Petey 08-01-2008 10:15 PM

Are you in NYC?

Tell your Uncle to do the right thing and listen to your parents? Or is he too cocky?
Sorry, but he sounds like a hack.

fungku 08-02-2008 04:14 AM

Where I live you need to run a ground :P

If it's done properly with the connectors and locknuts, etc. it should be safe using metal conduit as ground, but that is not acceptable practice and that makes perfect sense to me.

it sounds like this guy is a goof. Why not call the local electrical inspector and see what his opinion is? :whistling2:

Ash 08-02-2008 04:19 AM

Go install an earth wire. at the very least add it in parallel outside the conduit (idk if it is ok from the code point of view but it is at least safer)

jrclen 08-02-2008 10:06 AM

If the uncle is installing EMT and AC and connecting and supporting it per code and it's listed, he is doing a code compliant job. Grounding conductors are great, but not required. If I had to go back and install green wires in all the conduit I have installed, I would run out of years long before I ran out of conduit. :whistling2:

I do hope the job is being done with a permit and will be inspected.

Stubbie 08-02-2008 10:48 AM

I agree with two concepts here.... one is what Chris said... if the conduit is existing he would run a equipment ground in the conduit. The second is what Jrclen said if he installed the conduit and knowing the proper fittings and connection methods he would be fine without a redundant equipment ground inside the metallic raceway. Your uncle is correct however done properly it isn't needed. However the receptacles need to be done properly also. It is not necessarily adequate to just install a receptacle in a metal box without a bonding jumper from the receptacle green screw to the box. We would need to know if he is using self grounding receptacles and the type of box or mounting them on raised covers (mudrings) that screw to the box.. etc..

But the real issue is what you say here.......

Quote:

The worse part is that my parents have asked him to run a ground wire, but he refuses to run it, and says they have nothing to worry about (this being before he was very far along in the project).
This would be where uncle gets fired IMO.

Stubbie

J. V. 08-02-2008 12:42 PM

Quote:

Originally Posted by stringtheories (Post 145068)
Hes doing things like running conduit through holes hes punching in ductwork to get it through to places he wants it to be, and up the corner of closets and stuff like that.

As far the grounding goes, the others are correct. He does not need to pull a ground in most instances.
Some jurisdictions do require the "EGC" ground wire in conduit. So check your local authority.

He cannot punch holes through ductwork to put the conduit through. This is a violation of the NEC.
(I am not certain if this is a correct statement, but I am checking on it at this very moment) edited today 08.03.08.

Visible conduit in the closets is okay, but IMO it is not something a good craftsman would do.

Updated 08.05.08
According to article 300.22 NEC 2005, conduit is allowed to be installed in air ducts. So I retract the statement above, and apologize for any inconvenience incurred. jrclen is credited for the correction.


All times are GMT -5. The time now is 10:02 AM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved