Service Conduit Bond

[shoon]

Just ran my first 200A overhead service and was wondering about bonding of the conduit connecting the load side of the meter box to the main panel.
Specifically- wondering if there is any advantages or disadvantages to bonding the service conduit within the main panel vs to the meter base enclosure.

Inspector wanted the conduit bond to be made to the meter base enclosure instead of inside the main panel. I figured keeping the bond connection in the main panel was advantageous since it was one more connection that could still be visible / accessible without having to remove the POCO meter from the meter base. Functionality wise, I imagine both methods get the job done.

 

[GoldDigger]

Just ran my first 200A overhead service and was wondering about bonding of the conduit connecting the load side of the meter box to the main panel.
Specifically- wondering if there is any advantages or disadvantages to bonding the service conduit within the main panel vs to the meter base enclosure.

Inspector wanted the conduit bond to be made to the meter base enclosure instead of inside the main panel. I figured keeping the bond connection in the main panel was advantageous since it was one more connection that could still be visible / accessible without having to remove the POCO meter from the meter base. Functionality wise, I imagine both methods get the job done.

Both methods get the job done, but some POCOs will not allow the bonding to take place in "their" meter base.

 

[infinity]

We've done it both ways as the NEC allows either method. Sometimes it's just easier in the meter enclosure.

 

[meternerd]

Both methods get the job done, but some POCOs will not allow the bonding to take place in "their" meter base.

I don't know of any utilities that would not allow a conduit bond in their meter enclosure. If I'm not mistaken, all metallic conduits and raceways require bonding on the line side of the service disconnect. The issue for some is the connection of the GEC inside the POCO sealed section.

 

[kwired]

Some utilities want a ground rod connected to the meter socket regardless of what other electrodes you may have connected at the service disconnect.

I would likely bond at the service equipment in most instances partly because there often is no open lug to land the bonding jumper on in the meter socket.

 

[packersparky]

I would use PVC and not worry about having to bond the conduit.

 

[Smart $]

...lug to land the bonding jumper...

It amazes me how many resort to installing a bonding bushing with a jumper when installing a bonding locknut is a compliant viable option.

 

[infinity]

It amazes me how many resort to installing a bonding bushing with a jumper when installing a bonding locknut is a compliant viable option.

You're correct that's a cheaper and faster option and some cases that will work but for a 200 amp service the raceway is likely to be 2". Some meter enclosures and panels come with 2.5" KO's so the bonding locknut won't work.

 

[Smart $]

You're correct that's a cheaper and faster option and some cases that will work but for a 200 amp service the raceway is likely to be 2". Some meter enclosures and panels come with 2.5" KO's so the bonding locknut won't work.

That is correct. They cannot be used where one encounters concentric, eccentric KO's larger than the conduit size... for services and some non-service equipment. They are permitted for non-service equipment where the box has concentric, eccentric KO's and is listed to provide a reliable bonding connection (FWIW, I don't know of any offhand). See 250.97 Exception.

 

[electrofelon]

I would use PVC and not worry about having to bond the conduit.

Generally I would to, however sometimes there is a space restriction in a back to back setup so a nipple is necessary. In that case, if the meter had 2.5" ko, a 2.5" nipple and bonding locknut as smart suggested would be a good plan.