Overhead service drop jurisdiction

[jackson]

In Michael Holt's book, 'Understanding the National Electrical Code', 3rd Edition:

He states, 'Overhead service drop conductors from the electric utility must be installed in accordance with the NESC, and are exempted from the requirements of the NEC, 90-2(b)(5)'.

Why does the NEC have service drop clearance requirements? Which agencies determines if requirements are met?

Thank you.

 

[jumper]

The mast,POA, service conductor size to the POA and height clearances are NEC.

The size of the POCO tranny and conductor size to the tranny is NESC. POCO can undersize, we cannot.

They attach a 1/0 to our 4/0 for a 200 amp resi service and run the heck out of their tranny.

 

[Smart $]

...

Why does the NEC have service drop clearance requirements? Which agencies determines if requirements are met?

Whether covered by NESC or NEC is determined by the Service Point (see Article 100 Definitions). Typical Service Point location is at the connection to Service Entrance conductors... but not always. Additionally, last time I checked, NESC and NEC Service Drop clearance requirements are identical.

The AHJ determines compliance... (i.e. which agency varies by state and locality).

 

[Hv&Lv]

We have some accounts in our territory that the point of delivery is at the CT's above a 4160 platform bank. From there the customer is responsible for all transformers, poles, and wiring, whether overhead or underground. All this wiring past our point of delivery is under the jurisdiction of the NEC.

 

[1793]

In my area the POCO is now requiring the POA being higher than what the NEC calls for.

I would to know if anyone has the NESC Standard 02 10 10 close at hand, this is what owr POCO's Handbook is referencing for "Service Conductor to Ground Clearance."

 

[Hv&Lv]

In my area the POCO is now requiring the POA being higher than what the NEC calls for.

I would to know if anyone has the NESC Standard 02 10 10 close at hand, this is what owr POCO's Handbook is referencing for "Service Conductor to Ground Clearance."

I have the c2-2007 and c2-2011. Not sure what the 02 10 10 is...
However, the NESC table 232-1 (vertical clearances of wires, conductors and cables above ground, roadway, rail, or water surfaces) Lists the minimum height of the service wires depending on the surface the conductors are over. These height requirements are based on the "belly" of the wire, so the actual point of attachment will have to be higher to accommodate sag in the conductors.
Also, for Cooperatives, the government ruling agency, RUS, requires that the conductors exceed the NESC by one foot before the release of funds for construction.

 

[1793]

I have the c2-2007 and c2-2011. Not sure what the 02 10 10 is...
However, the NESC table 232-1 (vertical clearances of wires, conductors and cables above ground, roadway, rail, or water surfaces) Lists the minimum height of the service wires depending on the surface the conductors are over. These height requirements are based on the "belly" of the wire, so the actual point of attachment will have to be higher to accommodate sag in the conductors.
Also, for Cooperatives, the government ruling agency, RUS, requires that the conductors exceed the NESC by one foot before the release of funds for construction.

Our Handbook uses the Standard 02 10 10, it very well may not be a Standard of the NESC. However I still don't have access to the NESC c2-2011. This particular installation is over a grass area of a SFD. If someone would let me know the "Ground to Conductor" for this install would be greatly appreciated.

 

[Hv&Lv]

Our Handbook uses the Standard 02 10 10, it very well may not be a Standard of the NESC. However I still don't have access to the NESC c2-2011. This particular installation is over a grass area of a SFD. If someone would let me know the "Ground to Conductor" for this install would be greatly appreciated.

Table 232-1 NESC C2-2011: "Spaces and ways subject to pedestrians or restricted traffic only" (side yard fit this criteria) 12 ft.(the same as the NEC) There is a note that will allow the clearance to be reduced to 10.5 ft. IF the residential building does not permit its service drop to meet these values.

Remember, these measurements are taken at the lowest point of clearance. (the belly of the wire, or the high point of a ridge in the grass area, or both)

 

[1793]

Table 232-1 NESC C2-2011: "Spaces and ways subject to pedestrians or restricted traffic only" (side yard fit this criteria) 12 ft.(the same as the NEC) There is a note that will allow the clearance to be reduced to 10.5 ft. IF the residential building does not permit its service drop to meet these values.

Remember, these measurements are taken at the lowest point of clearance. (the belly of the wire, or the high point of a ridge in the grass area, or both)

Great.

Thanks a lot for your time and efforts :thumbsup:

 

[renosteinke]

What rules apply is determined by the AHJ- and the PoCo counts as an AHJ.

In practical terms, I have seen PoCo and NEC requirements come closer together over the years. Indeed, the PoCo standards will often reference the NEC.

Still, the PoCo requirements for mast support, etc., are often quite a bit more specific than the NEC.

It's also worth remembering that not every 'overhead service drop' is under the control of any utility provider. There are plenty of farms out there that have overhead wires between various buildings. There are plenty of trailer parks with their own private metering and distribution networks. So, there is a role for the NEC ... but they're not the only player.