Bonding meter can

[Robbie Romex]

I recently had a local inspector flunk a new service because I bonded the meter can to the service. Reading Art. 250-92(a) (1999 NEC) tells me to bond everything metal with service conductors in it. I was told that the power company here in CT doesn't like this article and we have to do as they say. Can anyone explain this to me? (I don't buy the bonded neutral explanation.)

 

[peter d]

Re: Bonding meter can

I assume you must be dealing with CL&P? You have to follow their rules. They don't allow the GEC connection in the meter can. End of story.

Now, that being said it's a stupid rule. In fact, the meter can is the best place to connect the GEC because it will divert a lighting strike or unintentional contact to the ground rods before entering the building.

 

[peter d]

Re: Bonding meter can

By the way, the good ole Socialist State of Connecticut is now using the 2005 NEC. Time to put the 1999 on the shelf.

 

[Robbie Romex]

Re: Bonding meter can

Thanks, can you spot me 60 bucks?

 

[peter d]

Re: Bonding meter can

Originally posted by Robbie Romex:
Thanks, can you spot me 60 bucks?

I need to go get the 2005 myself.

Where in CT are you?

 

[paul]

Re: Bonding meter can

Here in the Socialist Republic of Washington we bond the neutral to the GEC at the service disconnect.

 

[peter d]

Re: Bonding meter can

Robbie, as I think about this a few questions come to mind.

1) Did you run a bond wire from the meter can to the service panel or disconnect? If so, this creates a parallel path for neutral current to flow. The meter can does not require additional bonding as the metal can is allready bonded to the service neutral via the internal connection.

2) Or did you simply run your GEC connecting to your grounding electrodes directly to the meter can bypassing the service equipment entirely?

 

[magoo66]

Re: Bonding meter can

I was taught that the neutral - grounded conductor - is your "ground" until the first OC device. Hence a grounding electrode connection at a meter main and no grounding electrode for a regular meter socket. The regular socket is bonded via the green screw that the neutrals land on.

 

[Robbie Romex]

Re: Bonding meter can

The bonding screw is fine until something bad happens and the power company loses it's neutral. In such a case (admittedly unlikely) and when the meter can is isolated by pvc conduit there is no path to ground creating a very hazardous condition. To answer the other question, I ran a continuous bond from the first means of disconnect (in this case a transfer switch) through the meter can and to ground rods, creating equal potential wherever service conductors are present. By the way, in our newly required continuing ed. classes, we were told that meter cans must be bonded per 250-92.

 

[Robbie Romex]

Re: Bonding meter can

Torrington

 

[iwire]

Re: Bonding meter can

Robbie what do you mean by bonded?

I have never seen a meter can that the neutral is not factory bonded to the enclosure.

I am getting the impression you want to run another conductor (GEC?) to the meter can to bond it again.

 

[iwire]

Re: Bonding meter can

Originally posted by Robbie Romex:
I ran a continuous bond from the first means of disconnect (in this case a transfer switch) through the meter can and to ground rods, creating equal potential wherever service conductors are present.

Your disconnect is ahead of your meter?

 

[peter d]

Re: Bonding meter can

Oh, Torrington, you mean the middle of nowhere?

By the way, in our newly required continuing ed. classes, we were told that meter cans must be bonded per 250-92.

How did they recommend this bonding be accomplished? I have learned there are some real hacks teaching classes in CT.

 

[roger]

Re: Bonding meter can

Originally posted by Robbie Romex:
The bonding screw is fine until something bad happens and the power company loses it's neutral. In such a case (admittedly unlikely) and when the meter can is isolated by pvc conduit there is no path to ground creating a very hazardous condition.

Robbie, there is a path to ground which creates the biggest hazard in your scenario.

All though the graphic below is not directly addressing a lost neutral at the service equipment, the results would basically be the same.

Back to the original point, see the picture below for the GEC landed in the meter, which I believe is the best method.

Admitedly, the GEC could be landed in the Panel or Switch and have the same results, but seeing how the GEC's main function is to help disperse surges and Lightning, I like to see it outside the building.

Roger

 

[magoo66]

Re: Bonding meter can

Having the gec connection inside of the meter can makes it "inaccessable" here without poco presence.

 

[roger]

Re: Bonding meter can

Originally posted by magoo66:
Having the gec connection inside of the meter can makes it "inaccessable" here without poco presence.

Why would it need to be accessed any more than the other 6 (or 8 if three phase) connections in the Meter can?

Roger

 

[roger]

Re: Bonding meter can

Dadburnit, I hate it when the page rolls over.

Be sure to visit the last posts on page one.

Roger

 

[iwire]

Re: Bonding meter can

Originally posted by roger:
Admittedly, the GEC could be landed in the Panel or Switch and have the same results, but seeing how the GEC's main function is to help disperse surges and Lightning, I like to see it outside the building.
Roger

It does seem counter productive to run the lightning current into the building only to try to send it back out of the building. :roll:

 

[peter d]

Re: Bonding meter can

For some reason, some utilities have this phobia about connecting anything other than the power conductors in the meter enclosure.

Other utilites don't mind at all if you connect the GEC in there. I like those utilities.

 

[roger]

Re: Bonding meter can

Hello Bob,

Originally posted by iwire:

It does seem counter productive to run the lightning current into the building only to try to send it back out of the building.

Roger