luckylerado
Senior Member
- Location
- Lake of the Ozarks
This can only refer to conduits running parallel with the roof right? We are not supposed to apply this to the service masts now I hope.
2008 NFPA 70
310.15(B)(2)(c)
"Conduits Exposed to Sunlight on Rooftops. Where
conductors or cables are installed in conduits exposed to
direct sunlight on or above rooftops, the adjustments shown
in Table 310.15(B)(2)(c) shall be added to the outdoor temperature
to determine the applicable ambient temperature
for application of the correction factors in Table 310.16 and
Table 310.18."
Table 310.15(B)(2)(c) Ambient Temperature Adjustment for
Conduits Exposed to Sunlight On or Above Rooftops
Temperature Adder
Distance Above Roof to Bottom of
Conduit ?C ?F
0 ? 13 mm (1⁄2 in.) 33 60
Above 13 mm (1⁄2 in.) ? 90 mm (31⁄2 in.) 22 40
Above 90 mm (31⁄2 in.) ? 300 mm (12 in.) 17 30
Above 300 mm (12 in.) ? 900 mm
(36 in.)
14 25
2008 NFPA 70
310.15(B)(2)(c)
"Conduits Exposed to Sunlight on Rooftops. Where
conductors or cables are installed in conduits exposed to
direct sunlight on or above rooftops, the adjustments shown
in Table 310.15(B)(2)(c) shall be added to the outdoor temperature
to determine the applicable ambient temperature
for application of the correction factors in Table 310.16 and
Table 310.18."
Table 310.15(B)(2)(c) Ambient Temperature Adjustment for
Conduits Exposed to Sunlight On or Above Rooftops
Temperature Adder
Distance Above Roof to Bottom of
Conduit ?C ?F
0 ? 13 mm (1⁄2 in.) 33 60
Above 13 mm (1⁄2 in.) ? 90 mm (31⁄2 in.) 22 40
Above 90 mm (31⁄2 in.) ? 300 mm (12 in.) 17 30
Above 300 mm (12 in.) ? 900 mm
(36 in.)
14 25
