BONDING

[iwire]

Re: BONDING

Originally posted by websparky:
The code permits the grounded conductor to be bonded to the meter can even if there is a metalic connection via conduit between it and the service disconnect, right?

Darn right.

Originally posted by websparky:
However, you are pointing out that if this is the case, you will have a parallel path for "neutral" and "fault" current, right?

Yes and no, this thread keeps drifting around but look back far enough this was about requiring a bond wire between a meter and a service panel when there is PVC or SE between them.

With PVC or SE used between the service panel and the meter socket a bonding wire is pointless and a violation of 310.4.

If you run a metallic conduit between the service panel and the meter socket and that conduit basically becomes a neutral conductor as shown in Eds drawing.

The code will not allow this between a SDS source and the first disconnect.

Also the code will not allow this between two structures.

To me it is an oddity that this is allowed (metallic conduit) between two bonded enclosures.

 

[roger]

Re: BONDING

Hello Dave, that is correct. Believe it or not, this issue was one of the first things I questioned as an apprentice.

Roger

 

[bennie]

Re: BONDING

What is the harm with parallel paths between the meter and main?

 

[iwire]

Re: BONDING

What are the benefits?

 

[roger]

Re: BONDING

Bennie, if either of the conductors can carry the maximum load on their own nothing.

Personaly I would rather have something other than locknuts being the sole connection of the neutral conductor.

As Bob questions, is there any benefit?

Roger

 

[rasmithircgov.com]

Re: BONDING

I thought you couldn't use just locknuts to bond service raceways?
250.92 Services.
(A) Bonding of Services.
(B) Method of Bonding at the Service. Electrical continuity at service equipment, service raceways, and service conductor enclosures shall be ensured by one of the following methods:
(1) Bonding equipment to the grounded service conductor in a manner provided in 250.8
(2) Connections utilizing threaded couplings or threaded bosses on enclosures where made up wrenchtight
(3) Threadless couplings and connectors where made up tight for metal raceways and metal-clad cables
(4) Other approved devices, such as bonding-type locknuts and bushings
Question what is a threadless coupling and connector I've never seen one I think.We make them bond them using bonding locknuts etc. etc. Am I wrong? Am I missing something?

[ April 06, 2004, 04:09 PM: Message edited by: rasmithircgov.com ]

 

[websparky]

Re: BONDING

Do you mean like this?

 

[apauling]

Re: BONDING

This may seem late but I am back to discuss the points I asserted earlier. tried to log on last night and this am but there were problems.

The short answer to all the questions is a diagram in the 99 NEC handbook, fig 250.11, with two disconnects, with numerous "paralleling" bonds, since bonding locknuts are shown, it is assumed that the conduit is metallic/conducting.

The longer answer to all the other questions starting with using the meter as the disconnect in a residence.

1. A meter cannot be used as a dwelling disconnect, as the homeowners cannot be assumed to have knowledge and access to disconnect power in a max of six moves. meter may even be locked.
99NEC, 225-32, 225-33,225-35, 225-38, 230-70, 230-77, and many more.

There is a difference between grounding and bonding and all service equipment and piping and enclosures must be both bonded and grounded. The "non-current carrying metallic systems " must also be bonded to the grounding system. There are no exemptions from this double hit for electrical connections. from the handbook there is another figure, 250.30 which shows the options being discussed. At 250-92, &at 250-94 we see that all the comonents MUST be bonded and grounded, that the piping system must be electrically continuous with the panel bodies and both the grounded conductor and the grounding conductor are connected to the enclosure bodies.

there should be no more need to discuss this.

The inspector was right.

 

[roger]

Re: BONDING

Paul, the more you try to defend your stance, the more you flounder. Where do you get the idea anyone is saying the meter is a disconnect, it is simply a meter and doesn't change anything.


You have some talented and experienced people questioning your stand and you aren't doing a very good or convincing job of explaining it.


BTW, you should also know that the handbook commentary can't be enforced as code, and as an inspector you should not be using it to argue your point.

Roger

[ April 06, 2004, 09:08 PM: Message edited by: roger ]

 

[apauling]

Re: BONDING

roger, have you noticed that others are questioning YOUR stance. Iwire said he considered the meter the disconnect. maybe you haven't read the thread as well as you thought.

On another thread, "multiple disconnects", a power provider gave a drawing about the grounded conductor connections in a metallic, electrically continuous panel. They support my contention that the NEC considers the metallic portions of the enclosures as "non-current carrying".

I am not personally bothered by your lack of understanding of grounding and bonding. It is obvious that you consider yourself right by being that last man arguing. The truth is that we may just tire of trying to help you.

Grounding and bonding cannot be disregarded unless specifically stated. It must be proven that objectionanble currents exist on the ground, rather than asserting they do theoretically, before tampering with multiple grounding connections. It is unlikely the objectionable currents exist in SFD's.

Just the idea that the defendents of your position run unfused and unprotected cable (not in conduit) into a SFD convinces most the rest of us that it is an old, outdated, and extremely hazardous ideas that are driving the defense of this install.

you can have the last argue, bark away

 

[iwire]

Re: BONDING

Originally posted by apauling:
Iwire said he considered the meter the disconnect.

Please enlighten me, where did I say the meter is disconnect?

You have not provided any code references to back your position.

Bob

[ April 07, 2004, 04:29 AM: Message edited by: iwire ]

 

[don_resqcapt19]

Re: BONDING

Paul,

there should be no more need to discuss this.
The inspector was right.

No, the inspector was not right. There is no need or requirement to install an equipment bonding jumper through the PVC nipple in parallel with the grounded conductor.
Don

 

[eprice]

Re: BONDING

The inspector was not right. 250.92(B)(1) specifically allows this bonding to the grounded service conductor.

 

[apauling]

Re: BONDING

250-92-b-1 says that the bonding can be done with a metalic raceway. The metallic raceway was missing and the inspector required a bond be run in it's stead. he should of have just failed it.

iwire, I reread all the posts and where you said yes and i thought you were saying yes to disconnect, you were saying that the above metallic raceway was a parallel circuit. my apologies.

it does NOT say that the bond of the service enclosures can be the grounded neutral. The service enclosures must be electrically continuous.

so looooong

 

[roger]

Re: BONDING

Paul, how many times are you going to say something to this effect "so looooong, good bye, I'm done, there's no sense in discussing this , bla bla bla"?

It's obvious that you are going to ignore anything someone says that contradicts your "I've always done it this way" so it must be right attitude.

You're loosing credibility with every post.

Roger

[ April 07, 2004, 01:26 PM: Message edited by: roger ]

 

[don_resqcapt19]

Re: BONDING

Paul,

250-92-b-1 says that the bonding can be done with a metalic raceway. The metallic raceway was missing and the inspector required a bond be run in it's stead. he should of have just failed it.

While using the metal raceway to bond service equipment is permitted by the code, it is not the only permitted method. 250.92(B)(1) very clearly permits the use of the grounded conductor to bond the service equipment. The inspector was wrong to fail this installation.
250.24(B) requires that the grounded conductor be bonded to the service disconnect enclosure. The grounded conductor is bonded to the enclosure of every meter can that I have ever come across. This is all of the bonding that is required by the code.
If a bonding jumper would be intalled it would be in parallel with the gounded conductor and of a smaller size. What purpose would it serve?
Don

 

[peter d]

Re: BONDING

Just the idea that the defendents of your position run unfused and unprotected cable (not in conduit) into a SFD convinces most the rest of us that it is an old, outdated, and extremely hazardous ideas that are driving the defense of this install.

If I read this correctly, are you saying that service cable is one of these ideas that is "old, outdated, and extremely hazardous"?

Please provide evidence that using service cable is hazardous.

I can't speak for the others here, but where Bob (Iwire) and I come from, service cable is used every day of the week in hundreds of installations. It is not likely to change anytime soon, and if it does, there will be a lot of people fighting that change.

 

[iwire]

Re: BONDING

Originally posted by apauling:
Just the idea that the defendents of your position run unfused and unprotected cable (not in conduit) into a SFD convinces most the rest of us that it is an old, outdated, and extremely hazardous ideas that are driving the defense of this install.

That is an interesting position.

I am trying to grasp what you are saying.

Cable called Service Entrance Cable is not suitable for service entrance conductors because it is not in conduit.

A wiring method that is currently recognized by the NEC and has an article devoted to it is old and outdated.

A wiring method that is being installed daily is extremely hazardous.

I am Licensed in MA, RI and CT, SE is an acceptable method in these States, I guess they are all behind the times and need an inspector like yourself to show them the light.