Service Conductors Through Roof

Two are insulated hot cables each carrying 120 volts of electricity.

Service conductors through roof.

For 120 208v or 120 240v service drop conductors overhead conductor clearances from the roof can be reduced 3 feet if the slope of the roof exceeds 4 inches for every 12 inches. Overhead service conductors must maintain a minimum clearance of 8 ft above the surface of a roof for a minimum distance of 3 ft in all directions from the edge of the roof. The pole is called the mast or riser and it contains a large cable or individual wires known as the service entrance conductors or service entrance cable. One of the exceptions is the most common type of residential overhead electric service type so we will start with it.

A standard service drop includes three cables or conductors. Where the roof has a slope of 4 inches 102 mm in 12 inches 305 mm or greater the minimum clearance shall be 3 feet 914 mm. These conductors exit the mast through the weatherhead which is shaped so that the conductors slant downward as they come out. Does not exceed 300 a reduction in clearance above only.

Conductors above a roof surface subject to pedestrian traffic shall have a vertical clearance from the roof surface in accordance with section e3604 2 2. 4 in in 300 mm 12 in or greater a reduction in clearance. The service drop is either anchored to a metal pole rising through the roof or attached to the exterior of the house. To 900 mm 3 ft shall be permitted.

You re required to install service drop conductors so they aren t readily accessible and they must comply with several clearance requirements. Where the voltage between conductors. The minimum clearance above only the overhanging portion of the roof shall not be less than 18 inches 457 mm where not more than 6 feet 1829 mm of overhead service conductor length passes over 4. A third cable usually bare uninsulated aluminum serves as the neutral conductor and provides structural support for the entire service drop.

The national electric code nec 230 24 a requires that overhead service wires conductors be a minimum of 8 feet above a roof including for a minimum 3 feet in all directions from the edge of the roof but then provides four allowable exceptions.