SynC · Topic
These are the standards in the SynC Standards library that cover Circuit Breakers. Each one is a complete, plain-language specification: the scope it applies to, the requirements that govern it, and a structured equipment datasheet listing the values a project has to decide — ratings, materials, setpoints, and the standards each is verified against. All of it is free to read without an account and published under CC BY-SA 4.0.
A standard usually carries several topics, so most of the entries below also appear under neighbouring subjects. The topics each one carries are listed on its own page.
Dead-front, free-standing low voltage distribution switchboards rated 600V and below, built to UL 891 and NEMA PB 2, with group-mounted molded-case or insulated-case circuit breakers (fixed-mounted or individually drawout). Covers service entrance and downstream distribution boards for commercial, institutional, and industrial facilities.
Metal-enclosed, low voltage power circuit breaker switchgear rated 600V and below for commercial, institutional, and industrial facilities. Covers indoor and outdoor configurations with drawout power circuit breakers.
Metal-clad medium-voltage switchgear rated above 1 kV through 38 kV using drawout vacuum or SF6 circuit breakers, built to IEEE C37.20.2 and the ANSI/IEEE C37.04 / C37.06 / C37.09 series, for utility-customer substations, large commercial campuses, healthcare and higher-education central plants, data centers, and industrial facilities. Covers 5 kV, 15 kV, 27 kV, and 38 kV voltage classes, indoor and outdoor walk-in (protected aisle) configurations, arc-resistant ratings per IEEE C37.20.7, multifunction microprocessor protective relays, and optional IEC 61850 station bus communications.
A time-current coordination study for low- and medium-voltage power distribution systems rated 38 kV and below, where multiple overcurrent protective devices are installed in series and selective operation is required. Covers the analysis, settings recommendations, and deliverables that demonstrate the closest upstream protective device to a fault opens first, leaving the rest of the system energized. Includes coordination of relays, low-voltage power circuit breakers, molded-case and insulated-case breakers, fuses, and motor starter overload elements; coordination with transformer through-fault damage curves, conductor damage curves, and motor starting and inrush envelopes; and the dedicated selective-coordination requirements of NEC 700.27 and 701.27 for emergency and legally required standby systems.