PT-100 Manual

Page 31

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).