Meter Pan Grounding

Status
Not open for further replies.
New construction with a meter pan, generator automatic transfer switch (ATS) and main breaker panel all on an outside wall with PVC nipples connecting all three metal enclosures. Utility service is underground. The neutral bus in the meter pan is bolted/bonded directly to the meter pan enclosure.

I have it currently wired a shown in Meter Pan 1 drawing. With it wired this way I have a parallel neutral connection between the meter pan and the ATS. So I think I should remove the bonding jumper between the meter pan and the ATS as shown in Meter Pan 2 drawing. The POCO's Service Specification Book appears to show that it should be wired as shown in Meter Pan 3 drawing.

I looked at 250.24 and it says the MBJ needs to be in the enclosure with the service disconnect but I don't see where it says the GEC needs to be in that same enclosure, just that it needs to be connected to the grounded service conductor somewhere between where the underground service comes into the meter pan and the first disconnect. They say it needs to be "accessible" which sounds like the meter pan would be "accessible" even with the POCO wire lock on it since it doesn't say "readily accessible". Thoughts?
 

Attachments

  • Meter Pan 1.jpg
    Meter Pan 1.jpg
    66.1 KB · Views: 21
  • Meter Pan 2.jpg
    Meter Pan 2.jpg
    65.1 KB · Views: 21
  • Meter Pan 3.jpg
    Meter Pan 3.jpg
    64.4 KB · Views: 19

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
The paralleled neutral connection is permitted on the line side of the service disconnect which is in the ATS. Around here GEC connections are not permitted in the meter enclosure by the POCO.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
There is no need for two neutral conductors between the meter and the ATS.
You're correct, I missed the part about PVC nipples and thought that he had a parallel path created by metallic nipples which would be permitted. The way it's shown in diagram #1 is a violation of 250.6.
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
We could use 2 or 3 here, depending on the POCO. Some require the GEC in the meter, some won't allow it in there, and one will allow either in or out.
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
About all I see here is #3.
I think an inspector here would be surprised to NOT see one done like #3
 
Status
Not open for further replies.
Top