Grollor33
Electrical
- Apr 20, 2005
- 28
Hi all,
I was wondering if anyone could tell off the top of their head why IEC 60909's Method B uses a 15% multiplier when estimating the symmetrical fault current??
I'm under the impression that the X/R ratio used by IEC is from a combined R & X network reduction. Is the 15% adjusted symmetrical fault current used to cover any conservativism in network reduction (before applying factors to estimate the asymmetrical)?
Even though 60909 is older, my short cirucuit analysis program uses it and I would like to know what I'm dealing with. Any help would be appreciated!! Thanks a lot!
jweav33
I was wondering if anyone could tell off the top of their head why IEC 60909's Method B uses a 15% multiplier when estimating the symmetrical fault current??
I'm under the impression that the X/R ratio used by IEC is from a combined R & X network reduction. Is the 15% adjusted symmetrical fault current used to cover any conservativism in network reduction (before applying factors to estimate the asymmetrical)?
Even though 60909 is older, my short cirucuit analysis program uses it and I would like to know what I'm dealing with. Any help would be appreciated!! Thanks a lot!
jweav33