Protective device (Mtive) MTIVE = Mean time between failure for the protective device See Also Protected function (Mted) MTED = Mean time between failure for the protected function See Also Allowed time between multiple failures (Mmf) MMF = Allowed mean time between multiple failures See Also Number of parallel protective devices (n) n = the number of parallel protective devices See Also Required to activate system (k) k = number of protective devices required to activate the system See Also Units which have to be in a failed state (r) r = the number of units which have to be in a failed state in order to cause the whole system to fail: r = n - k + 1 See Also
