Air Circuit Breakers (ACBs): Used in main LV distribution boards for high fault interrupting capacity. The National Electric Reliability Council (NERC) has reported that 70% of outages in electric power systems are due to protection-related issues. Distribution systems need protection against overcurrent and overvoltage. Adequate system designs allow for the system to withstand and isolate faults while not causing additional damage and/or outages. High voltages and currents, if not properly managed, can lead to system faults, equipment damage, fire hazards, and even fatal accidents. The human body, for instance, can generally tolerate currents below 50 milliamperes. Inside a standard distribution board, key components such as the main switch, MCBs, RCDs, Surge Protection Devices (SPDs), busbars, and terminals work together to protect sensitive equipment and improve safety. Circuit breakers and RCDs alone don't provide complete protection—they handle. EPRI has been exploring protective device configuration approaches tar-geted at minimizing the chances of adverse interactions with the power system and the environment.
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