Circuit breaker device and method of triggering the circuit breaker device if current and voltage threshold values are exceeded in a time window

A circuit breaker for protecting an electrical low-voltage circuit having conductors, comprising:

• a housing having connections for the conductors of the electrical low-voltage circuit;
• a current sensor to ascertain a level of a current of the electrical low-voltage circuit, with a result that current values are available;
• a voltage sensor to ascertain a level of a voltage of the electrical low-voltage circuit, with a result that voltage values are available;
• an electronic interruption unit having semiconductor-based switching elements and, as a result of said semiconductor-based switching elements, said electronic interruption unit has a high-impedance state for said semiconductor-based switching elements for a purpose of interruption and a low-impedance state for said semiconductor-based switching elements for a purpose of current flow in the electrical low-voltage circuit;
• a controller connected to said current sensor, to said voltage sensor and to said electronic interruption unit;
• the circuit breaker is configured such that the current values are used to ascertain a change in current over time, with a result:
• that current change values are available cyclically;
• that the voltage values and an expected value for the voltage are used to ascertain a difference voltage, with a result that difference voltage values are available cyclically;
• that each of the difference voltage values is compared with a first threshold value;
• that each of the current change values is compared with a second threshold value;
• and
• that the interruption of the electrical low-voltage circuit is initiated if the first and second threshold values are exceeded within a first time window.