Ungrounded AFCI?

[physis]

Re: Ungrounded AFCI?

Can you tell me why you think that is true and point to the codes?

Edit: Error B

[ July 06, 2005, 03:59 PM: Message edited by: physis ]

 

[iwire]

Re: Ungrounded AFCI?

Originally posted by jwelectric:
Hello my name is Mike??. I am a post-a-holic

Many of us are.

Sam I agree with Mike that the NEC absolutely will not allow any stand alone electrode to be used as the sole grounding means for any installation.

250.4(A)(5) Effective Ground-Fault Current Path. Electrical equipment and wiring and other electrically conductive material likely to become energized shall be installed in a manner that creates a permanent, low-impedance circuit capable of safely carrying the maximum ground-fault current likely to be imposed on it from any point on the wiring system where a ground fault may occur to the electrical supply source. The earth shall not be used as the sole equipment grounding conductor or effective ground-fault current path.

You may use the grounding electrode system which by definition is connected to the panels grounding bus.

 

[iwire]

Re: Ungrounded AFCI?

Originally posted by physis:
250.130(C). Like I said, my post on the last page.

Sam where in 250.30(C) do you see that you can use a stand alone electrode?

250.130(C) Nongrounding Receptacle Replacement or Branch Circuit Extensions. The equipment grounding conductor of a grounding-type receptacle or a branch-circuit extension shall be permitted to be connected to any of the following:

(1)Any accessible point on the grounding electrode system as described in 250.50

(2)Any accessible point on the grounding electrode conductor

(3)The equipment grounding terminal bar within the enclosure where the branch circuit for the receptacle or branch circuit originates

(4)For grounded systems, the grounded service conductor within the service equipment enclosure

(5)For ungrounded systems, the grounding terminal bar within the service equipment enclosure

Basically the choices are the grounding electrode system or the Grounding electrode conductor.

Both of those by NEC definition are connected to the panels grounding bus.

 

[physis]

Re: Ungrounded AFCI?

Ok, I'll buy 250.4(A)(5). That's good. And it doesn't even have to conflict with the permission in 250.130(C).

 

[jwelectric]

Re: Ungrounded AFCI?

Originally posted by physis:
Can you tell me why you think that is true and point to the codes?

Edit: Error B

250.130 Equipment Grounding Conductor Connections.
Equipment grounding conductor connections at the source of separately derived systems shall be made in accordance with 250.30(A)(1). Equipment grounding conductor connections at service equipment shall be made as indicated in 250.130(A) or (B). For replacement of non?grounding-type receptacles with grounding-type receptacles and for branch-circuit extensions only in existing installations that do not have an equipment grounding conductor in the branch circuit, connections shall be permitted as indicated in 250.130(C).

Through out this thread references have been made to 250.130 (C) with out taking a look at 250.130.

I have said many times in this forum that the biggest mistake I see with electricians and inspectors is they look at part of a section and forget the rest of that section.

Before we look a (C) it would be wise to read (A) which has been over looked from the start (me included). Here is what (A) has to say, ? For Grounded Systems. The connection shall be made by bonding the equipment grounding conductor to the grounded service conductor and the grounding electrode conductor.?

Now if I have a grounding electrode weather installed at the time of the service or I just installed it, it must be bonded to the grounded (neutral).

How was that?
Hello my name is Mike ?.. I am a post-a-holic

 

[jwelectric]

Re: Ungrounded AFCI?

Damn you all are fast

 

[physis]

Re: Ungrounded AFCI?

JW, if you go to page 6 you'll see where I point out that 250.130 is where you get permission to use 250.130(C).

And you still didn't address the question.

And if you didn't write such long posts we wouldn't pass you up as much.

 

[iwire]

Re: Ungrounded AFCI?

Originally posted by physis:
I'd like to this definition you're talking about.

You will have to apply two sections to see the expectation of a GES (grounding electrode system)

250.24 Grounding Service-Supplied Alternating-Current Systems.
(A) System Grounding Connections. A premises wiring system supplied by a grounded ac service shall have a grounding electrode conductor connected to the grounded service conductor, at each service, in accordance with 250.24(A)(1) through (A)(5).

(1) General. The connection shall be made at any accessible point from the load end of the service drop or service lateral to and including the terminal or bus to which the grounded service conductor is connected at the service disconnecting means.

250.50 Grounding Electrode System.
If available on the premises at each building or structure served, each item in 250.52(A)(1) through (A)(6) shall be bonded together to form the grounding electrode system. Where none of these electrodes are available, one or more of the electrodes specified in 250.52(A)(4) through (A)(7) shall be installed and used.

 

[physis]

Re: Ungrounded AFCI?

From your own post you can clearly see that the grounding electrode system is described all by itself. Completely independant of any connection to the service.

 

[jwelectric]

Re: Ungrounded AFCI?

Those outlined by Bob
and
250.130 Equipment Grounding Conductor Connections.
(A) For Grounded Systems. The connection shall be made by bonding the equipment grounding conductor to the grounded service conductor and the grounding electrode conductor.

 

[physis]

Re: Ungrounded AFCI?

(A)'s a different application than (C). My question was regarding a groundless building.

 

[iwire]

Re: Ungrounded AFCI?

Originally posted by physis:
(A)'s a different application than (C). My question was regarding a groundless building.

What the heck is a groundless building?

You can have a ungrounded service but you still must have a grounding electrode system. 250.24(D)

And thanks Mike for the added reference, I assumed Sam would know that the GES must be connected to the service.

 

[physis]

Re: Ungrounded AFCI?

Alright. An existing building with no EGC's.

You know, those older ones.

 

[iwire]

Re: Ungrounded AFCI?

Originally posted by physis:
Alright. An existing building with no EGC's.

You know, those older ones.

Oh.. but I still not sure what your driving at.

Even in an old building with all two wire circuits there should still be a grounding electrode system in place.

 

[physis]

Re: Ungrounded AFCI?

Would there be?

I'm kind of assuming there was time when there weren't elctrodes systems. ?

Edit: I'm not driving at anything just pointing out to JW that I was thalking about 205.130(C) not (A).

[ July 06, 2005, 05:11 PM: Message edited by: physis ]

 

[iwire]

Re: Ungrounded AFCI?

Originally posted by physis:
Would there be?

I'm kind of assuming there was time when there weren't elctrodes systems. ?

Sam I think grounding electrodes have always been desired going back to the earliest distribution systems.

When they became required, the requirement enforced or the old time DIYs started to include them is up for question.

If the GES in not already there you can not connect to it.


Bob

 

[physis]

Re: Ungrounded AFCI?

If you choose to install a GES just so you can connect to it via 250.130(C) IMO it goes without saying that this newly installed GES would have to in fact be a code compliant GES.

I wouldn't argue with you a bit there. I agree.

But you can't enforce axioms.

Edit: Not that you'd need to for this one.

[ July 06, 2005, 05:45 PM: Message edited by: physis ]

 

[George Stolz]

Re: Ungrounded AFCI?

Originally posted by iwire:

Originally posted by georgestolz:
Where is the hazard?

There is a real hazard in what you describe.

If the neutral opens on the old circuit all the items 'grounded' in the new circuit will have hot enclosures.

No one will like touching the shiny new appliance.

Wait a tick: wouldn't that be possible for a properly grounded system anyway? I've had half a beer and a long day, so I might be having a moment.

 

[physis]

Re: Ungrounded AFCI?

The lost neutral senario is a popular one. Of course a lot of bad things are gonna happen with no neutral.

 

[George Stolz]

Re: Ungrounded AFCI?

I think 100 VCR's can bite the dust, but making an unsafe situation for one person should be avoided at all costs.