A three phase short circuit fault can be split into two states, an asymmetrical state and a symmetrical state. The Peak fault occurs first during the asymmetrical state and is the maximum possible instantaneous value of the short circuit current. The RMS fault occurs after the Peak fault and is the latter more symmetrical state of the short circuit. RMS is the square root of the mean of the squares of the values of these two states.

Peak short circuit – ip

‘maximum possible instantaneous value of the short circuit current’

Initial RMS symmetrical short circuit current – I”_k

‘RMS value of the a.c. symmetrical component of a short circuit current, applicable at the instant of the short circuit if the impedance remains at the zero-time value’

Decaying (aperiodic) component of short circuit current – id.c

‘mean value between the top and bottom envelope of a Short circuit current decaying from an initial value to zero’

Steady-state short circuit current – I _k

‘RMS value of the Short circuit current which remains after the decay of the transient phenomena’

CMP short circuit testing

All CMP Products cable cleats have been tested and certified according to the latest IEC 61914:2009 standard before their release to the market.