Full Size EGC

[ActionDave]

....Even the best conduit on the other hand gets wrecked when the other trades go into drop ceilings and inadvertently break apart everything.

You've seen a lot of this have you?

 

[LarryFine]

Right. But beyond a circuit length the impedance still adds up, particularly on the hot.

Absolutely, but that has nothing to do with the wire-vs-conduit-EGC debate.

That's more of a sub-panels-and-feeders-vs-long-branch-circuits discussion.

 

[mbrooke]

Absolutely, but that has nothing to do with the wire-vs-conduit-EGC debate.

That's more of a sub-panels-and-feeders-vs-long-branch-circuits discussion.

I guess you could say that.

You've seen a lot of this have you?

Have you ever been in a drop ceiling, particularity in a place with high turn over?

 

[mbrooke]

I am rather fascinated by how and when this wire EGC obsession started. It was well before I started in the late 90's.

People have slowly been becoming knowledgable realizing that code is wrong/inadequate.

 

[ActionDave]

Have you ever been in a drop ceiling, particularity in a place with high turn over?

Have you?

 

[mbrooke]

Have you?

I have. Conduit is to easily seperated from its fittings.

 

[ActionDave]

I have. Conduit is to easily seperated from its fittings.

Your occupation says Electricity, not Electrician. What kind of work experience do you have working on conduit installations?

 

[mbrooke]

Your occupation says Electricity, not Electrician. What kind of work experience do you have working on conduit installations?

I'm out of service work at the moment. But I've seen enough to form an opinion.

 

[mbrooke]

Your occupation says Electricity, not Electrician. What kind of work experience do you have working on conduit installations?

Here are what some EEs say about it:








I would take their advice and forget about the Z of conduit, but I only care about it in that if a knicked hot touched conduit between two j-boxes that the breaker actually clear.

 

[tortuga]

Anyone do full size EGCs for circuits up to 60 amps?


View attachment 2556327
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The EGC is not bonded to the metal box.

What you never size your EGCs to Table 54.3?


View attachment 2556329

This table from the British standard is more like our 250.66 it is not used for branch circuits.
The minimum size EGC in BS 7671 for a branch circuit is a 2.5mm2 wich is about a 13 AWG.
The 16 mm2 amounts to a 5 awg.
I will say it is a nice table.

 

[mbrooke]

The EGC is not bonded to the metal box.

Even if the ground terminal has a strap to the metal yoke plate?

This table from the British standard is more like our 250.66 it is not used for branch circuits.
The minimum size EGC in BS 7671 for a branch circuit is a 2.5mm2 wich is about a 13 AWG.
The 16 mm2 amounts to a 5 awg.
I will say it is a nice table.

Basically a full size EGC for circuits up to 60 amps, half size beyond that. It guarantees that the EGC will not fuse or melt under exceptionally high short circuit currents or during delayed clearing. Also reduces touch voltage.

The painful reality is that we need to have a discussion about Table 250.122...

 

[ActionDave]

I'm out of service work at the moment. But I've seen enough to form an opinion.

Here are what some EEs say about it:


I would take their advice and forget about the Z of conduit, but I only care about it in that if a knicked hot touched conduit between two j-boxes that the breaker actually clear.

I think I understand now. If you want to form an opinion based on a bunch of stuff you read on the internet then that's fine. The Cult of the Green Wire has taken over a lot of minds in the electrical industry.

 

[mbrooke]

I think I understand now. If you want to form an opinion based on a bunch of stuff you read on the internet then that's fine. The Cult of the Green Wire has taken over a lot of minds in the electrical industry.

The cult exists for good reason. The blunt truth is the NFPA did and does not understand fault clearing, and thus befuddling electricians.

 

[LarryFine]

Even if the ground terminal has a strap to the metal yoke plate?

Correct. With a self-grounding yoke, the EGC connection to the device is optional; the connection to the box is mandatory.

 

[mbrooke]

Correct. With a self-grounding yoke, the EGC connection to the device is optional; the connection to the box is mandatory.

Can't you hit the receptacle first, then use the yoke to hit the box?

 

[LarryFine]

Can't you hit the receptacle first, then use the yoke to hit the box?

No. That's what I'm saying.

 

[Little Bill]

Can't you hit the receptacle first, then use the yoke to hit the box?

No

 

[mbrooke]

No

Code section?

 

[mbrooke]

No. That's what I'm saying.

Bummer Makes no sense though.

 

[romex jockey]

If you have a metal casing, it should be capable of clearing for a shorting hot. Thats why I think all MC cable needs a bond strip.

b-b-b-b-ut....said casing is wound, and actually 5-6X's the length of it's encapsulated conductors

~Z~ matters , thus the bond strip.....


~RJ~