Conduit accepted as ground.

[Mark Horner]

NEC says that conduit can be used as the ground,I`m not sure sure how this could be at all acceptable due to the vulnerability of the connection that is easily susceptible to being disrupted,can someone explain to me about this?

 

[infinity]

Are you an electrician?

 

[rnatalie]

Why do you think it's any more likely to be disrupted than any other conductor?

 

[Besoeker3]

Why do you think it's any more likely to be disrupted than any other conductor?

Steel as opposed to copper conductors. And screw threads can loosen.

 

[480sparky]

Properly installed metallic raceways can continue to serve as a solid grounding conductor for decades.

Sloppily installed metallic raceways; meh... not to reliable.

So go to 110.3(b) and 110.12(B) and you have your answer.

 

[LarryFine]

Steel as opposed to copper conductors. And screw threads can loosen.

The size of conduit needed to enclose a given set of conductors has a lower impedance than the grounding conductor that would otherwise be used with them.

 

[Buck Parrish]

Check out NEC 300.6 -7 8-9-10-12 Those areas. Other than that and above mentioned you're getting in to "what if's" and that can go on forever.

 

[mbrooke]

The NEC is a litigation based document. Meaning there need to be enough documented cases of a latent hazard playing out to actually sway voting for a proposal. Money under the table aside.

Yes conduit connections can become loose, but it tends to be masked by all the parallel metallic paths in many commercial buildings.

 

[Besoeker3]

The size of conduit needed to enclose a given set of conductors has a lower impedance than the grounding conductor that would otherwise be used with them.

Just the way we do it. Conduit just isn't acceptable here. In fact we hardly use any conduit. The odd straight length for am appliance socket (switch) and that is invariably PVC, not EMT.

 

[mbrooke]

Just the way we do it. Conduit just isn't acceptable here. In fact we hardly use any conduit. The odd straight length for am appliance socket (switch) and that is invariably PVC, not EMT.

My gripe is when you run the CPC separate from the SWA or trunking. Reactance goes way up when you do that and I hear R1+R2 not taking it into account all to often. But I digress

 

[LarryFine]

My gripe is when you run the CPC separate from the SWA or trunking. Reactance goes way up when you do that and I hear R1+R2 not taking it into account all to often. But I digress

 

[Besoeker3]

My gripe is when you run the CPC separate from the SWA or trunking. Reactance goes way up when you do that and I hear R1+R2 not taking it into account all to often. But I digress

Remind me about CPC?

 

[mbrooke]

Remind me about CPC?

Circuit protective conductor, earth or ground wire. I see pics on forums where its run separate at times.

 

[Besoeker3]

Circuit protective conductor, earth or ground wire. I see pics on forums where its run separate at times.

Ah, OK. Not really my forte.

 

[Mark Horner]

Are you an electrician?

yes i am

 

[Mark Horner]

Why do you think it's any more likely to be disrupted than any other conductor?

corrosion between couplings or connectors or even loose locknuts

 

[tom baker]

NEC says that conduit can be used as the ground,I`m not sure sure how this could be at all acceptable due to the vulnerability of the connection that is easily susceptible to being disrupted,can someone explain to me about this?

You can certainly put in a proposal to require a wire type EGC in a metal raceway, your proposal (or PI) would be for the 2026 NEC, plenty of time to gather documentation. Past proposals to require wire type EGC have been rejected with the comment that properly installed RMC, EMT, IMC is an acceptable EGC, Keep in mind who is on the CMP, take a look at CMP No. 8.

 

[tom baker]

corrosion between couplings or connectors or even loose locknuts

For corrosion, section 300,6 directly addresses this. Loose locknuts is an installation issue.
The NEC is a minimum standard.
I recognize and agree with what you are saying, and I most of the time would install an wire type EGC.
Again look at the CMP for panel 8.

 

[Mark Horner]

Properly installed metallic raceways can continue to serve as a solid grounding conductor for decades.

Sloppily installed metallic raceways; meh... not to reliable.

So go to 110.3(b) and 110.12(B) and you have your answer.

my point exactly,even properly installed could corode as well.

 

[infinity]

Are you an electrician?

yes i am

Thank you for responding. Can you please add your occupation to your profile?