ASHRAE Handbook - Fundamentals?

[tx2step]

Does anyone have a link to the average ambient temperatures (high temperatures) that would be used to determine the correct ambient temperature correction factor in Table 310.15(B)(2)(A)?

The two areas I'm mainly interested in are Dallas, TX and southwest Oklahoma.

Thanks for the help!

 

[bphgravity]

There are three (3) locations provided for Dallas. You have Dallas Love Field, Dallas Hensley Field NAS, & Dallas / Fort Worth. The temperatures listed below are nearly identical to southwest OK.

The 2% average for June - August is 98 - 99 degrees F.

The 30 year max. temp. = 109 - 112 degrees F.

Raceways above roof temp: 1/2" = 159 degress F., 3-1/2" = 139 degrees F., 12" = 129 degrees F., 36"= 124 degrees F.

 

[RICK NAPIER]

The Copper Developement Ass. has a web site that is handy.

http://www.copper.org/applications/electrical/building/derating.html

 

[tx2step]

Thanks to both of you! That helped!

To avoid the ampacity derating required by 310.15(B)(3)(c) "Circular raceways exposed to sunlight on rooftops", & Table 310.15(B)(3)(c) -- have you seen a shade installed over the conduits? I've been thinking of puting 1"x4" boards or maybe sheetmetal strips lengthwise over the conduits to shade them. Have either of you seen something done like that? Any thoughts about it?

Does 310.15(B)(3)(c) apply to conduits mounted on a parapet wall that adjoins (but is above) a rooftop? If it does, would some type of shade eliminate the additional temperature derating?