This handbook highlights 2020 NEC changes for circuit protection, covering fault current, interrupting ratings, SCCR, and selective coordination requirements.
This handbook provides an overview of the 2020 National Electrical Code (NEC) changes specifically pertaining to circuit protection. It addresses key areas such as fault current definitions, available fault current, interrupting ratings, and equipment short-circuit current ratings (SCCR). The document aims to improve terminology consistency and add prescriptive requirements for verifying overcurrent protective device ratings at the point of installation.
Fault current flows when a short-circuit condition occurs on an energized circuit and leaves the normal circuit conduction path.
The failure can result in catastrophic, violent explosions which are a serious fire and shock hazard.