Where must the service disconnecting means be installed?
- At a readily accessible spot nearest the conductor entry
- At any point inside, if the conductors are in conduit
- At the most central location within the building
- At the panelboard that serves the largest load
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A. At a readily accessible spot nearest the conductor entry
The service disconnect goes in a readily accessible location outside the building or inside nearest the point where the service conductors enter. Service conductors have no overcurrent protection at their supply end, so their length inside the building is kept short.
Reference: NEC 2023, 230.70(A)(1)
What is the minimum clearance of 120/240 V overhead service conductors above a residential driveway?
- 10 ft
- 12 ft
- 15 ft
- 18 ft
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B. 12 ft
Over residential property and driveways, with voltage not over 300 to ground, the clearance is 12 ft. The 10 ft figure applies above finished grade and sidewalks accessible only to pedestrians.
Reference: NEC 2023, 230.24(B)
What is the minimum clearance of overhead service conductors above a public street subject to truck traffic?
- 10 ft
- 12 ft
- 15 ft
- 18 ft
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D. 18 ft
Public streets, alleys, roads and parking areas subject to truck traffic call for 18 ft. The 12 ft and 15 ft clearances are for residential and other areas not subject to truck traffic.
Reference: NEC 2023, 230.24(B)