Overload protection Overload protection aims to protect conductors from the thermal effects of passing more current than they are rated for. Here the current flowing is higher than the nominal current, however not high enough to be classified as a short circuit fault. For instance, where a 630A circuit breaker will trip in 1 hour when passing 650A and will trip in 1 minute when passi... https://www.cleantechcontrols.com.au/protection-in-electrical-switchboards-overcurrent-protection/