• Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by first logging in then clicking here: Upgrades

Splitting a 400amp Service

I was just curious which one covered a wire in parallel with a raceway. Either this doesn't apply or every HFC installation in the country is a violation of several of those rules. (material, length, size etc). The references to 250.122 in (6) clearly do not apply since we use 250.66 for bonding on service conductors.
 
gfretwell said:
I was just curious which one covered a wire in parallel with a raceway. Either this doesn't apply or every HFC installation in the country is a violation of several of those rules. (material, length, size etc).
Click to expand...
I feel sure that you know the difference between a raceway and a conductor. The conductors goes into the raceway. 310.10 addresses the conductors and the conductors is what I am addressing.
gfretwell said:
The references to 250.122 in (6) clearly do not apply since we use 250.66 for bonding on service conductors.
Click to expand...
Equipment grounding conductors are covered in 5 not 6. 6 covers equipment bonding conductors and any conductor on the line side of the service will be an equipment bonding conductor not an equipment grounding conductor.Althouhg a metal raceway between the meter base and the service disconnect enclosure constitures a parallel path the raceway is not a condutor as mentioned in this thread, it is a raceway, therefore not subject to 310.10 as any conductor installed in the raceway would be would be.
 
it is a raceway, therefore not subject to 310.10 as any conductor installed in the raceway would be would be.
Click to expand...
I suppose that is why I was confused about the 310.10 reference in the first place, looking at the picture. I can see you might bring it up if there was a green/bare wire in the pipe.

I do understand there is some controversy about parallel paths but I think NFPA has avoided looking at that within the various components of service equipment, having the single path concerns only on the load side of the service disconnect. 250.24(5).
 
The original picture is of a service to which BSSTG made the comment that an equipment grounding conductor need to be installed.

I commented that this would be in violation of 310.10(H) and Paul made a comment to the listing of the meter can and of the dangers of using metal pipe between the two.

Then you posted the Handbook picture making comments about metal pipes and the NFPA not caring about rebonding. How did you get confused?

Maybe it is because some think that a meter can is part of the service equipment. The meter be it an inline meter or a CT meter is nothing more than a cash register for the power company, a wide spot in the service conductors. It is not part of the service equipment.

We bond the equipment grounding conductors to the neutral at the same point where we have the ability to turn off all the current flow to the building.

We do not have the ability to turn off the power any other place other than at the service disconnect therefore this is where this bonding takes place.

Anything that is happening before the service disconnect is not grounding unless it is a connection to earth but instead it is bonding which is not concerned with an earth connection but instead is concerned with fault current. There is a BIG difference between the two.

As to the connection of the grounding electrode which has nothing to do with fault current, this connection can take place at the weather head or the grounding bar in the service equipment or any point in between, see 250.24.

Around here the #6 to the ground rods takes place in the meter can and the water pipe or CEE takes place in the service equipment. The neutral ties the two together. The grounding electrode system is installed for four reasons and fault current is not found in that section of the codes, see 250.4(A)(1).

Merry Christmas
 
Greetings,

Well I stand corrected. In doing some digging I ran across this article from EC&M. It states that bonding is not required when the conduit from the meter can to the panel is PVC. That said, if the conduit is metal then it is required to be bonded with groundling bushings or locknuts around concentric KO"s and so forth. They are saying that it's ok for the meter can to be bonded via the neutral with nothing else required with the PVC. I suspect the reasoning for this is that if a fault were to occur in metal conduit then it would need be bonded since it will carry current. If it were to have a fault in PVC there would be no need to be bonded as the pipe wouldn't be energized.

This is contrary to the research I did a few years back when this very subject came up. What I found was that not all meter cans were considered bonded when the neutral was made up with no additional bonding when PVC was the load side conduit. I also looked at quite a few meter cans and it was iffy for them to be self bonding as the screws did not appear to make up 2 full threads and did not look to comply with 250.8 otherwise. Meter can listings were dubious as well.

This is not an issue where I'm at as the electical provider will not turn on power without direct grounding connections in the meter can to the GEC. Additionally, our local ordinance requires ground wires in all conduits regardless. I don't know who but it in there but it takes a lot of guesswork out of the grounding/bonding question.

Here is the link that I found helpful.

Grounding and Bonding

Happy New Year!

BSSTG
 
Last edited by a moderator:
I suspect PoCos started bonding in the can when the PVC SE raceway showed up. That avoids all of the parallel neutral thing if someone ran a green wire.
 
You must log in or register to reply here.
Top