Altitude Derating

[LionelHutz]

Hello,

Are there any good references or standards for altitude deratings for switchgear? I've seen some info in IEEE/ANSI C37.20.3-2001 but that's about the only standard with altitude derating info that I have found.

 

[dpc]

Manufacturers generally cover this in their literature. You might check with your favorite vendor. In US, I'd check with Cutler Hammer or maybe here:

http://www.powl.com/main/Uploadpdf/pv_ag.pdf

There are two issues - the dielectric rating and the continuous current rating. The derating factors are different for each.

 

[cuky2000]

See the enclose information:

http://cuky2000.250free.com/Altitude Derating factor 2.jpg

http://cuky2000.250free.com/Altitude_Derating_Factors1.jpg

Paraphrasing Yogi Berra, engineering is 90% technical and the other half is administrative.

 

[TMD]

This link may help.

http://www.teledynereynolds.com/product/1singlepin/other/page42.asp