Safety Breaker Symbol. It detects small stray voltages on the metal enclosures of electrical equipment and interrupts the circuit if a dangerous voltage is detected. Pi and pt instrument connections on piping shall be i s w unless otherwise noteo.
This symbol represents circuit breaker with three poles. E an earth leakage circuit breaker elcb is a safety device used in electrical installations with high earth impedance to prevent shock. It detects small stray voltages on the metal enclosures of electrical equipment and interrupts the circuit if a dangerous voltage is detected.
Commonly used p id symbols piping and instrumentation diagram symbols for safety valves.
It connects three phases whenever there is an overload or short circuit in any phase the circuit breaker trips all three phases simultaneously. This symbol represents circuit breaker with three poles. Such kind of breakers is used in three phase systems in industries. 1200 a identifies the drawout circuit breaker represented by the symbol as a 1200 ampere circuit breaker.
