Abstract: A circuit-breaker includes an electronic trip unit, which initiates an interruption or reduction of the current flow in a low-voltage circuit when current or current-time limits are exceeded in the low-voltage circuit. The electronic trip unit includes at least two processors that independently check whether current or current-time limits are being exceeded. A test signal is fed to the circuit-breaker via a first communication interface, which is fed to one of the two processors during operation so that a test of the circuit-breaker is carried out during operation, while at the same time an active protection is provided with regard to the exceeding of current or current-time limits.

Abstract: A circuit-breaker includes an electronic trip unit, which initiates an interruption or reduction of the current flow in a low-voltage circuit when current or current-time limits are exceeded in the low-voltage circuit. The electronic trip unit includes at least two processors that independently check whether current or current-time limits are being exceeded. A test signal is fed to the circuit-breaker via a first communication interface, which is fed to one of the two processors during operation so that a test of the circuit-breaker is carried out during operation, while at the same time an active protection is provided with regard to the exceeding of current or current-time limits.

Abstract: A power switch includes an electronic overcurrent protection trigger, which receives the power supply thereof from the power supply network monitored by the power switch. In at least one embodiment, the display device of the power switch acquires the power supply thereof from the power supply network monitored by the power switch, and an electronic device powered with voltage from the power supply network monitored by the power switch controls the turning on and off of the background illumination of the electronic display device, which obtains the voltage supply thereof from the power supply network monitored by the power switch, with the aid of an electronically controllable switch as a function of the measured values detected in a measuring device of the electronic device. A method for controlling the turning on and off of the background illumination of a display device of a power switch is also disclosed.

Abstract: A method is disclosed for updating software of an electronic device, in particular of the release of low-voltage circuit breakers, whose software is stored in a nonvolatile storage area. In at least one embodiment of the method, the updated software is copied from an external carrier into this storage area. In order to ensure safe operation of the circuit breaker even after a software update, at least one embodiment of the invention proposes that the updated software which has been copied to this storage area is checked by way of an external test device, that the test device, in the event of updated software which has been copied without any faults, writes a fault-free identification to the/a nonvolatile storage area, and that the updated software is only started by the electronic device if the fault-free identification for the updated software is present.