malachi constant
Senior Member
- Location
- Minneapolis
Not sure whether this is a good forum to discuss arc flash studies/results, but here goes. I can post the SKM file if it helps.
Is it normal for available arc flash energy (cal/cm^2) to increase the further down the system you get?
For instance, at the main bus I've got 6.6 cal/cm^2.
15' of copper later, at the next bus I've got 14.4 cal/cm^2.
Out of curiousity I cloned a couple more buses and got...
15' later, at the 3rd bus, I've got 20.6 cal/cm^2.
15' later, at the 4th bus, I've got 22.4 cal/cm^2.
FWIW, the main is protected by a 1600A Littelfuse KLLU. System voltage is 208V 3P. This is the first round of studies I've done myself, and is typical for most of the facilities. This does not strike me as normal and I wonder if I'm doing something wrong...or maybe it is just normal.
Thanks!
Is it normal for available arc flash energy (cal/cm^2) to increase the further down the system you get?
For instance, at the main bus I've got 6.6 cal/cm^2.
15' of copper later, at the next bus I've got 14.4 cal/cm^2.
Out of curiousity I cloned a couple more buses and got...
15' later, at the 3rd bus, I've got 20.6 cal/cm^2.
15' later, at the 4th bus, I've got 22.4 cal/cm^2.
FWIW, the main is protected by a 1600A Littelfuse KLLU. System voltage is 208V 3P. This is the first round of studies I've done myself, and is typical for most of the facilities. This does not strike me as normal and I wonder if I'm doing something wrong...or maybe it is just normal.
Thanks!