titan wrote:
I have been using ETAP v7.1 and the descriptions for the labels for each arc-flash category seems to be inaccurate. Anyone else notice that? In some cases it says Cat 3 requires only a min ppe of 4. and Cat 1 requires a min PPE of 8.
I basically deleted those descriptions and just typed up what was in NFPA 70E 130.11? I don't remember if it was 130.. but I just used the descriptions in the NFPA 70E. Seems more accurate.
Anyone else came across this?
Good Catch! - Sounds like a potentially troublesome glitch. One more reason people can not "blindly" use software without understanding everything else about arc flash and studies.
I am not familiar with ETAP but I bet there is a data table somewhere within the S/W where you can make a change to the correlation of Categories and Incident Energy.
You are correct in using the NFPA 70E values, i.e.
Cat 1 = Minimum 4 cal/cm^2 PPE
Cat 2 = Minimum 8 cal/cm^2 PPE
Cat 3 = Minimum 25 cal/cm^2 PPE
Cat 4 = Minimum 40 cal/cm^2 PPE