Circuit breaker

IEC 60617 (single-line diagram symbols)

Drawn as

A switch (a lead with a diagonal blade) with a small × on the fixed contact.

Meaning

Circuit breaker that makes, carries and interrupts fault current: incomers, feeders and bus ties. Inside a switchboard it is part of switchgear. In an outdoor substation (air-insulated bay) it becomes hv-circuit-breaker.

Variants

ANSI legends draw a square box or two arcs; draw-out breakers show chevrons (» «) above and below
A filled square is often used for a closed breaker on SLD overviews