Ue: Rated voltage (690V) Ui: Rated insulation voltage (1000V) Uimp: Rated impulse withstand voltage (8KV) Common basic correlation symbols of circuit breakers and their meaning and relationship between them
Inm - circuit breaker shell class current A, which refers to the maximum switching and tripper current value that can be installed in this circuit breaker.
In - the rated current A of the circuit breaker, which refers to the rated thermal tripper current value selected in the circuit breaker, in the non-adjustable fixed thermal tripper, In=Ir1.
Ir1 – the long-delay setting current A of the circuit breaker, which refers to the current value set by the circuit breaker's overload protection tripper.
Ir2 - the short-delay setting current A of the circuit breaker, which refers to the short-delay setting current of the circuit breaker, its value is about 2~12Irl adjustable in the electronically adjustable tripper.
Ir3 - the instantaneous setting current of the circuit breaker A, it refers to the meaning of the circuit breaker instantaneous tripper setting current, its value in the non-adjustable fixed tripper, the distribution type is 5Irl, 10Irl two, the motor protection type is 12Ir1, in the electronic adjustable type, it is about 4~16Irl adjustable.
Ir4 - the single-phase grounding setting current of the circuit breaker A, which refers to the current value of the grounding protection tripper when a single-phase grounding fault occurs in the line or equipment protected by the circuit breaker, and its value is about 0.2~0.6Irl adjustable. Ire - the leakage action current A of the circuit breaker, which refers to the current value set by the leakage protection tripper when abnormal leakage current occurs in the line or equipment protected by the circuit breaker. Its values are 0.03/0.1/0.3/0.5A. Ir0 - circuit breaker pre-alarm action current A, it refers to the meaning that when the load current of the circuit breaker exceeds the pre-set current, the pre-alarm device sends an alarm indication signal, and its value is about 0.5~lIr1 can be adjusted. Ir2 - the setting value of the trip time of the short delay tripper s, the adjustable time is 0.05~0.45s.
