The present invention relates to a power supply and measuring device for an electronic device (e.g. an IED), which is configured to provide supervision, control, protection, communication and/or monitoring functionalities for LV or MV circuits or apparatuses. The power supply device comprises a current transformer, which is operatively associated to a main power line. An input section of the power supply device comprises a burden regulating stage that is configured to regulate the equivalent electric load at the secondary winding of said current transformer. An output section of the power supply device provides a supply voltage suitable to feed said electronic device.

A DC circuit breaker including a pair of arcing contact members for holding an arc, an interaction element, adapted for interacting with the arc in dependence of whether the arc is in a first or second state such that the arc voltage drop in the first state is lower than the drop in the second state, a resonance branch coupled in parallel to the contact members thereby forming a resonance circuit adapted for letting a resonance branch current I.sub.r oscillate thereby inducing oscillations of an arc current I.sub.a, wherein the resonance branch includes a coupling element for coupling the resonance branch with the arc, such that the arc is brought to the first state when the current I.sub.r in the resonance branch has a first direction, and that the arc is brought to the second state when the current I.sub.r in the resonance branch has a second direction.

A device connectable to a three-phase network, wherein the device includes a capacitor, a secondary coil, a diode and, per phase, a conductor and a circuit, where a secondary-side coil is connected in parallel to the capacitor via the diode, the circuit is configured such that a resistor is located in a conductor, a first capacitor is connected parallel to the resistor, a serial circuit of a first primary-side coil is connected in parallel to the first capacitor, energy transfer occurs from a first primary-side coil to a second primary-side coil and to the secondary-side coil, a second capacitor is connected in parallel to the second primary-side coil, the second capacitor is connected to the source connection of a self-conducting field effect transistor, and the gate connection of the self-conducting field effect transistor is connected to the second capacitor to provide an improved internal power supply for the device.

The disclosure relates to an electronic fuse system, and to a method for an electronic fuse system. The method comprises determining (201) if the number of engaged electronic circuit breaker modules (108) has changed compared to the stored configuration. Upon determining that the number of engaged electronic circuit breaker modules (108) has changed, determining (202) if the configuration of the electronic fuse system has changed by means of comparing a stored configuration in the power distribution controller (105) and a stored configuration in the electronic circuit breaker module (108). Upon determining that the configuration of the electronic fuse system has changed, determining (203) if a stored configuration is available from the bus (101). Upon determining (203) that a stored configuration is available from the bus, fetch (204) the stored configuration from the bus and start operation of the electronic fuse system according to the fetched configuration. Upon determining (203) that a stored configuration is not available from the bus, determining (205) if a stored configuration is available from the connectable external main processor. Upon determining (205) that a stored configuration is available from the connectable external main processor, fetch (206) the configuration from the connectable external main processor and start operation of the electronic fuse system according to the fetched configuration. Upon determining (205) that a stored configuration is not available from the connectable external main processor, start operation of the electronic fuse system according to a default configuration (207).

A solid-state circuit breaker for a DC power system which may operate unidirectional and bidirectional and does not require an external power supply to provide current interruption protection during an event of a short circuit fault.