NEC Scope

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VIC1958

Senior Member
Scenario:

City owned utility is running 12 Kv from their vault to their primary meter cabinet which is located on the exterior of the customers building. From the primary meter cabinet it is being piped inside to the customers transformer and then being stepped down. My questions is, where does the NEC come into play here?
 

GoldDigger

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Placerville, CA, USA
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If the customer owns the transformer(s), the service point would be somewhere between the meter cabinet and the transformer primary.
Where is the OCP for the 12kV?

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charlie b

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Lockport, IL
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Most likely at the point at which the transformer's primary conductors are connected to the metering cabinet. But you didn't say who owned the transformer, and who is installing the primary conductors. That would influence the answer.
 

VIC1958

Senior Member
City Utility will be pulling the primary conductors from their switches the City Utilities primary meter cabinet. From there, the customer will be pulling their own primary conductors to their own disconnect and then to their transformer.
 

GoldDigger

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Placerville, CA, USA
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The customer is definitely responsible for installing or confirming the OCPD protecting the primary of their transformer.
They may also be responsible for the protection and sizing of the meter to transformer conductors.
That would be done under NEC rules.
One thing I am not sure of is whether utility owned and maintained OCPD could be used to satisfy the NEC requirements for conductor and transformer protection.
For low voltage, I am pretty sure it cannot.
The disconnect you mentioned is fused, yes?

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Pharon

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Location
MA
The NEC should apply starting at the load side of the service disconnect.


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don_resqcapt19

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Location
Illinois
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The NEC applies starting at the load side of the service point...only the utility can tell you where the service point is.
 
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