isolated grounding conductor

[Dale001289]

Does the NEC allow a single, isolated grounding conductor to be routed (from the same panelboard) between several IG receptacles or does each receptacle require its own isolated grounding conductor?

 

[infinity]

You can use a single IG for multiple circuits just like a non-IG EGC. I've heard some argue that it won't be as effective using only one but the NEC doesn't care as this is a design parameter not a code requirement.

 

[ActionDave]

The NEC allows you as many or as few iso grounds as you want. One per pipe is sufficient for its purpose.

 

[Dale001289]

Thank you Infinity and ActionDave. Where is this section located in the NEC? (we are using the 2017 cycle)

 

[zbang]

some argue that it won't be as effective

I suspect more will argue that they're not effective at all (given how and where they're often used).

 

[Dale001289]

I suspect more will argue that they're not effective at all (given how and where they're often used).

Zbang, would you say the benefit of having the IG is more psychological vs technical ? Lol

 

[LarryFine]

Zbang, would you say the benefit of having the IG is more psychological vs technical ? Lol

These days, almost all electronic power supplies don't have cords with EGCs.

 

[hbiss]

That orange receptacle does look cool though.

-Hal

 

[zbang]

Zbang, would you say the benefit of having the IG is more psychological vs technical ? Lol

They certainly benefit the installer.

As Hal said, a lot of things now don't have/need an EGC now and twisted-pair Ethernet is already galvanicly isolated, so the entire purpose of an IG is irrelevant.

 

[infinity]

I suspect more will argue that they're not effective at all (given how and where they're often used).

I agree. There is 0 benefit in 2025. Unless told otherwise I would use a single IG for as many circuits as I could to waste as little money as possible.

 

[Dale001289]

All, Does article 517 change this discussion? Or should I consider the IG a dinosaur and move on?

 

[LarryFine]

As Hal said, a lot of things now don't have/need an EGC now . . .

Actually, that was me, but who's counting?

 

[ActionDave]

All, Does article 517 change this discussion? Or should I consider the IG a dinosaur and move on?

Art. 517 is about redundancy not anything about an IG. I pretty sure that some of the old IG requirements have been removed in the last two cycles.

 

[zbang]

Actually, that was me

Sorry there.

 

[Dale001289]

Art. 517 is about redundancy not anything about an IG. I pretty sure that some of the old IG requirements have been removed in the last two cycles.

We are using the 2017 NEC on this project - 517.16 talks to IGR’s.
But this is in reference to patient care so it probably doesn’t apply anyway

 

[Speedskater]

Skipping the rules part.
The IG conductor should follow the same path as the Hot & Neutral conductors.
The best plan is to Star out from a central junction box to all the receptacles and then a single cable back to the panel.

 

[hbiss]

Sorry there.

Don't be. I said the same thing many times in older posts.

-Hal

 

[ActionDave]

We are using the 2017 NEC on this project - 517.16 talks to IGR’s.
But this is in reference to patient care so it probably doesn’t apply anyway

Going off of memory - the IG receptacles are not allowed in patient care areas because they defeat the purpose of redundancy, i.e. the IG receptacle in the patient care area are more dangerous.

 

[Dale001289]

Skipping the rules part.
The IG conductor should follow the same path as the Hot & Neutral conductors.
The best plan is to Star out from a central junction box to all the receptacles and then a single cable back to the panel.

How about if we take one IG per circuit (to several receptacles) along with one EGC per circuit for along the same route from the panelboard ground bus?

 

[hbiss]

How about if we take one IG per circuit (to several receptacles) along with one EGC per circuit for along the same route from the panelboard ground bus?

Do whatever you want. Isn't going to amount to a hill of beans.

-Hal