Revised Question...Clearances NESC & NEC

[Lori D.]

Ok...no response to the previous question so let me try it this way.

I interpret both codes to say the service entrance conductor attachment point should be at a minimum height of 12'. Given a 2' drip loop lead on the service, the lowest point of the drip loop should be at 10'. Am I interpreting this correctly?

 

[jumper]

I would say: Depends. What is the voltage and application/area.

 

[jumper]

230.24 (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 driveways,
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, parking
areas subject to truck traffic, driveways on other
than residential property, and other land such as cultivated,
grazing, forest, and orchard

 

[Lori D.]

I am referring to residential services less than 300v to ground where the service conductor may or may not overhang a driveway and is not subject to commercial traffic.

 

[Dennis Alwon]

Ok...no response to the previous question so let me try it this way.

I interpret both codes to say the service entrance conductor attachment point should be at a minimum height of 12'. Given a 2' drip loop lead on the service, the lowest point of the drip loop should be at 10'. Am I interpreting this correctly?

I don't quite agree. There can be a situation where the overhead can be 10' above grade as well as the drip loop. Think of a wire running over a hill to a house where the house is lower than the hill. The overheads can be 10' where it is only accessible to pedestrians according to 230.24(B)(1) and the drip loop can still be at 10'

(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

 

[jxofaltrds]

Ok...no response to the previous question so let me try it this way.

I interpret both codes to say the service entrance conductor attachment point should be at a minimum height of 12'. Given a 2' drip loop lead on the service, the lowest point of the drip loop should be at 10'. Am I interpreting this correctly?

I do not have the NESC so I will only address the NEC.

230.36 allows the POA to be at 10'. Now the drip loop still has to meet 230.24(B) 10'.

Kind of hard to have the POA at 10'. Possible but not likely.

 

[K8MHZ]

Ok...no response to the previous question so let me try it this way.

I interpret both codes to say the service entrance conductor attachment point should be at a minimum height of 12'. Given a 2' drip loop lead on the service, the lowest point of the drip loop should be at 10'. Am I interpreting this correctly?

The only way to lose 2 feet of height with 2 feet of conductor would be to point it straight down. No way to make a loop like that!

Remember, the rules are for minimum heights. So long as they are complied with a discrepancy between them is moot. If both your POA and your conductor clearances are compliant it really doesn't matter if BOTH minimum requirements can be met at the bare minimum simultaneously or not.