Where Do I Bond?

[garyleeevans]

We Installed A Permanent Meter Pedestal Out By The Curb And Transformer And We Need To Feed A Large Garage/shop With A 100 A Panel And A Large Home, Both With Ufer Grounds. There Is No Metal Connecting The Two Buildings. The Pedestal Also Has A Ground Rod With 200 A Service.

 

[gndrod]

Hi Gary, Sounds like the 200A pedestal may have a split main disconnect for both structures? What is the overall load configuration. (shop-house-mobile sf etc.) Need a little data to see what you have. rbj, Seattle

 

[david]

230.40 Number of Service-Entrance Conductor Sets.
Exception No. 3: A single-family dwelling unit and a separate structure shall be permitted to have one set of service-entrance conductors run to each from a single service drop or lateral.

If ex 3 is your situation and If I understand correctly what you are asking then you need to bond the grounded service conductor to the service enclosure and you need to bond the grounding electrode conductor to the grounded conductor.

You need to let us know if you are running three wire or four wire service conductors to the two buildings from your meter pedestal.

 

[George Stolz]

What is the rating of the pedestal? You say you want 100A for the detached structure, and it is a large home. If the meter pedestal's panelboard is only rated at 200A, that might complicate things.

See 250.32(A) and (B). Option (B) gives you two methods for bonding and grounding. From what you describe, I'd be tempted to utilize (B)(2).

 

[Bill W]

Don't forget 250.24(5)(B) if your equipment ground is separated from your bonding point: often the case in larger distribution panels. The bonded tub should not be used to connect the equipment grounding bus to the grounding electrode.