Vertical clearance for service drop conductors 230.24 (B).

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darekelec

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Am I reading correctly that a driveway or any car traffic on commercial property bumps the hight of service drop conductors to 18’?
can I have only car traffic on commercial property and stay with 12’ clearance?

is it same for feeders?
Thank you in advance.
 
Feeders would be covered by 225.18. Think mostly similar to 230.24 but could be some differences.

Key to being able to use the 12 foot clearance is less than 300 volts to ground and no truck traffic. Over 300 volts pushes clearance to 15 feet. Truck traffic pushes clearance to 18 feet
 
darekelec said:
Am I reading correctly that a driveway or any car traffic on commercial property bumps the hight of service drop conductors to 18’?
can I have only car traffic on commercial property and stay with 12’ clearance?

is it same for feeders?
Thank you in advance.
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2017 NEC, Article 225.18(4) would indicate Yes, 18ft, "Driveways on other than residential properties ".
Most times in a commercial property the driveway is classified as public access, thus potentially entry by truck traffic possible, so the extra height, same as service entrance. Also measurement is from lowest point of line to road, driveway surface.
I suppose if local authorities agree to a restricted access an argument could be made for lesser height if point a to b heights create a hardship. But I would expect in such case they would say "bury it".
 
The heights of service drops are outside the scope of the NEC. They are covered by the NESC, the one that the utilities use. I believe that in most cases the two sets of rules match up, but not always.

If this is really a service drop and not "service conductors, overhead" you need to talk with your utility as they have jurisdiction.

In general, if the utility is installing the conductors they are a service drop, if the EC is installing them they are "service conductors, overhead".
 
don_resqcapt19 said:
The heights of service drops are outside the scope of the NEC. They are covered by the NESC, the one that the utilities use. I believe that in most cases the two sets of rules match up, but not always.

If this is really a service drop and not "service conductors, overhead" you need to talk with your utility as they have jurisdiction.

In general, if the utility is installing the conductors they are a service drop, if the EC is installing them they are "service conductors, overhead".
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Most the time yes it really is up to utility, most do apply NESC, not all apply it entirely either though.

Whether NEC actually applies does depend on the location of the "service point". There can be overhead service conductors on load side of service point and therefore is still a need for clearances in art 230.

But yes if this is "service drop" then by NEC definition this is on the supply side of the service point and it's installation is not covered by NEC.
 
(B) Vertical Clearance for Service-Drop Conductors.
Service-drop conductors, where not in excess of 600 volts, nominal, shall have the following minimum clearance from final grade:

(1) 3.0 m (10 ft) — at the electrical service entrance to buildings, also at the lowest point of the drip loop of the building electrical entrance, and above areas or sidewalks accessible only to pedestrians, measured from final grade or other accessible surface only for service-drop cables supported on and cabled together with a grounded bare messenger where the voltage does not exceed 150 volts to ground

(2) 3.7 m (12 ft) — over residential property and drive- ways, and those commercial areas not subject to truck traffic where the voltage does not exceed 300 volts to ground

(3) 4.5 m (15 ft) — for those areas listed in the 3.7-m (12-ft) classification where the voltage exceeds 300 volts to ground

(4) 5.5 m (18 ft) — over public streets, alleys, roads, park- ing areas subject to truck traffic, driveways on other than residential property, and other land such as culti- vated, grazing, forest, and orchard
 
I am on 2008 so the wording ‘service drop’ was used with a wrong meaning. It should have said: service conductors, overhead.
Am I right that
Clearance on Commercial property with pedestrians only is 10’ (120V to ground)
Clearance on commercial property with car only traffic is 12” (120 V to ground)
 
darekelec said:
I am on 2008 so the wording ‘service drop’ was used with a wrong meaning. It should have said: service conductors, overhead.
Am I right that
Clearance on Commercial property with pedestrians only is 10’ (120V to ground)
Clearance on commercial property with car only traffic is 12” (120 V to ground)
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Are sure? I just ask because service conductors overhead are quite rare in my experience.
 
I am sure 2008 doesn’t use the correct language
Maybe they cleaned it in later editions
On the same page they use

III. Underground Service-Lateral Conductors
 
"Service conductors, overhead" and "service conductors, underground" are on the load side of the service point and customer owned and installed. Service drops, and service laterals are on the line side of the service point and are utility owned and installed.
That code change was made to clarify what is customer owned and covered by the NEC and what is utility owned and covered by the NEC. The NEC starts at the service point, so service drops and service laterals are not covered by the rules found in the NEC.

Not sure why service drops and service laterals, are even in the NEC as they are outside the scope of the NEC.
 
Usually the POCO's determine the height of the service conductors not the NEC. In many townships where a residence is on the same side as the utility pole and houses are fairly close together they will allow you to locate the point of attachment at 10' on the house.. Here is a typical diagram from PSE&G in NJ but it's basically the same for all 3 POCO's in my area :

 
don_resqcapt19 said:
"Service conductors, overhead" and "service conductors, underground" are on the load side of the service point and customer owned and installed. Service drops, and service laterals are on the line side of the service point and are utility owned and installed.
That code change was made to clarify what is customer owned and covered by the NEC and what is utility owned and covered by the NEC. The NEC starts at the service point, so service drops and service laterals are not covered by the rules found in the NEC.

Not sure why service drops and service laterals, are even in the NEC as they are outside the scope of the NEC.
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I wasn't sure what year the changes happened but from what darekelec has mentioned it must have been 2008.

The whole key to all this was the addition of the term "service point" - which is the line between customer equipment covered by NEC and utility equipment not covered by NEC. Who own's or paid for what sort of doesn't matter it is what is deemed to be the "service point".

Service drops and laterals are not covered by the NEC requirements, but still come into play a little and nothing wrong with having said terminology to help identify what they are per usage of the code.

Laterals are a good example of where a transition from service lateral to service entrance conductors often occurs without any physical splice or joint in the conductors themselves.
 
kwired said:
The whole key to all this was the addition of the term "service point" - which is the line between customer equipment covered by NEC and utility equipment not covered by NEC. Who own's or paid for what sort of doesn't matter it is what is deemed to be the "service point".
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Around here the "service point" is also the ownership and who pays. Line side of the service point is on the utility, load side on the customer. So I use those terms interchangeably.
 
don_resqcapt19 said:
Around here the "service point" is also the ownership and who pays. Line side of the service point is on the utility, load side on the customer. So I use those terms interchangeably.
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Who owns what often factors in but is not definite everywhere.

Here some POCO's make you supply and install the conduit for service laterals, to their specifications, they pull conductors. The meter enclosure is generally the service point in those installations. POCO does agree to maintain/service that lateral should it need it.

Others, especially rural POCO's, should you need 4 miles of primary line constructed to supply you , you are paying for it, maybe not full cost but you are paying, it is still on supply side of wherever your service point is though. Sad part on this one is you pay that fee for those 4 miles then a few years later someone builds something across the road and a tap is made to this and they don't pay for anything but what they have added to the system. If the extension only crosses your private land you have more control though, they would need easement to tie onto it (more like to take anything away from the area already under easement), and you don't have to allow that easement if it is inside your property lines. Easement along borders they could take something that goes directly away from your property.
 
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