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©
2017 Sensata Technologies
Installation
Table 2-4, Rooftop Distance Adjustments
Distance Above Roof to Bottom
of Raceway or Cable
Temperature Adder
(°C)
(°F)
0 to 13 mm (0 to ½ in.)
33
60
Greater than 13 mm (½ in.) to 90 mm (3½ in.)
28
50
Greater than 300 mm (12 in.) to 900 mm (36 in.)
14
25
Data taken from Table 310.15(B)(3)(c) in the National Electrical Code® (2014 Edition)
Table 2-5, Multiple Conductors in Raceway/Cable Adjustments
Number of Conductors*
Conduit Fill Adjustment Factor
4 - 6
80% (0.80)
7 - 9
70% (0.70)
10 - 20
50% (0.50)
21 - 30
45% (0.45)
31 - 40
40% (0.40)
41 and above
35% (0.35)
Data taken from Table 310.15(B)(3)(a) in the National Electrical Code® (2014 Edition)
* Three current carrying conductors in conduit or bundled together in continuous lengths greater
than 24 inches (excludes grounding conductors).