fmtjfw
Senior Member
- Location
- Fairmont, WV, USA
I'm looking for constructive criticism on the following, and if you think it is merited, support in the form of comments from you on 3-183. Thanks, Jim Williams
4 Comment:
760.51 Number of Conductors in Cable Trays and Raceways, and Ampacity Adjustment Factors.
(B) Power-Supply Conductors and NPLFA Circuit Conductors. Where power-supply conductors and nonpower-limited fire alarm circuit conductors are permitted in a raceway in accordance with 760.48, the number of conductors shall be determined in accordance with 300.17. The ampacity adjustment factors given in 310.15(B)(3)(a) shall apply as follows: [ROP 3?183]
(1) To all conductors where the any fire alarm circuit conductors carry continuous loads in excess of 10 percent of the ampacity of each conductor and where the total number of conductors is more than three
(2) To the power-supply conductors only, where none of the fire alarm circuit conductors do not carry continuous loads in excess of 10 percent of the ampacity of each conductor and where the number of power-supply conductors is more than three
5 Statement of Problem and Substantiation.
The requirement for 10% or over current is not clear in either (1) or (2) as to whether it applies to some or all of the conductors.
The requirement for 3 or more conductors is unnecessary since there is no derating ? for count ? for 3 or less.
4 Comment:
760.51 Number of Conductors in Cable Trays and Raceways, and Ampacity Adjustment Factors.
(B) Power-Supply Conductors and NPLFA Circuit Conductors. Where power-supply conductors and nonpower-limited fire alarm circuit conductors are permitted in a raceway in accordance with 760.48, the number of conductors shall be determined in accordance with 300.17. The ampacity adjustment factors given in 310.15(B)(3)(a) shall apply as follows: [ROP 3?183]
(1) To all conductors where the any fire alarm circuit conductors carry continuous loads in excess of 10 percent of the ampacity of each conductor and where the total number of conductors is more than three
(2) To the power-supply conductors only, where none of the fire alarm circuit conductors do not carry continuous loads in excess of 10 percent of the ampacity of each conductor and where the number of power-supply conductors is more than three
5 Statement of Problem and Substantiation.
The requirement for 10% or over current is not clear in either (1) or (2) as to whether it applies to some or all of the conductors.
The requirement for 3 or more conductors is unnecessary since there is no derating ? for count ? for 3 or less.