A DC circuit breaker includes a fuse unit to interrupt a large current with a fuse, and the fuse unit includes a high-speed disconnector that is connected in parallel to the fuse and is opened when a fault current is detected.

The invention relates to a test device (1) for testing the insulation of an electrical line (2), in particular a cable or a cable harness, for detecting error points in the insulation of the electrical line (2). The test device (1) comprises a scalable, evacuable chamber (3) for completely accommodating the electrical line (2) to be tested, wherein at least one electrical connection point (6), preferably in the form of a plug device part, for connecting the electrical line (2) to be tested is arranged inside the chamber (3) and an electrical feedthrough (7) leads from the connection point (6) out of the chamber (3).

A system for detecting and indicating partial discharges and voltage. The system allows capturing signals from the electric power system and/or the electrical equipment thereof, and detecting and indicating the presence or absence of partial discharges and voltage, which allows carrying out a quick and simple inspection in order to prevent faults in the distribution elements, preventing risks and performing suitable installation maintenance.

A monitoring arrangement for electrical equipment includes a first sensor for sensing a surface creeping current on a creeping path-lengthening electrically insulating housing of the equipment. A monitoring system includes electrical equipment, the monitoring arrangement, a communication device for transmitting data to a central server device, and a central server device configured to receive and evaluate the data.

A method for detecting an abnormal event in an insulator of an electrical conductor of a medium-voltage or high-voltage electrical device. The method includes: acquiring a set of successive samples of a vibration signal associated with the electrical conductor; determining a modelled value of a following sample based on the acquired set of samples and on a prediction model, the prediction model being obtained through machine learning of the vibration signal based on a set of samples acquired in reference conditions in which the electrical conductor is free from any abnormal event; acquiring the following sample of the vibration signal; calculating a difference between the value of the acquired sample and the modelled value; and if the calculated difference is greater than a predetermined threshold, detecting an abnormal event in the electrical conductor.

Insulation monitoring may be provided by a signal generation unit for applying a pulse signal to an electric line; a signal measurement unit for measuring the voltage of an applied pulse signal from the ground, when the pulse signal is applied to the ground through insulation resistance; an average voltage calculation unit for calculating the average voltage of the voltages measured during a period depending on sampling intervals; and a control unit for calculating the sampling intervals on the basis of an initial sampling interval and a preset time multiple, calculating the average voltage during the sampling period according to the calculated sampling intervals, and, according to whether the difference between calculated first and second average voltages measured before the first average voltage is within a first error range, detecting the first average voltage as a normal voltage, or calculating the sampling intervals by applying different time multiples thereto.

A protection device configured for being electrically connected to a test tap of a HV bushing for protecting the bushing from transient overvoltages. The protection device includes at least two parallel connected protection branches connected between the test tap and a ground connector configured for connecting to ground. Each of the protection branches includes a plurality of parallel connected gas discharge tubes, a Transient-Voltage-Suppression (TVS) diode connected in series with the gas discharge tubes, and a resistor connected in series with the gas discharge tubes and across the TVS diode.

The embodiment of the present disclosure provides a cutout which can comprise a top contact assembly being capable of electrically coupled with a first electric cable; a bottom contact assembly being capable of electrically coupled with a second electric cable; an insulator assembly secured to the top contact assembly in a first end thereof, and secured to the bottom assembly in a second end thereof opposite to the first end; and a tube assembly having a fuselink placed therein for conducting electricity between the top contact assembly and a bottom contact assembly. The bottom contact assembly has a bottom contact member which is capable of electrically coupled with the second electrical cable at one end thereof, and removeably coupled with the tube assembly at the other end thereof, such that a current path is formed from the second electrical cable to the tube assembly via the bottom contact member.

The embodiment of the present disclosure provides a cutout which can comprise a top contact assembly being capable of electrically coupled with a first electric cable; a bottom contact assembly being capable of electrically coupled with a second electric cable; an insulator assembly secured to the top contact assembly in a first end thereof, and secured to the bottom assembly in a second end thereof opposite to the first end; and a tube assembly having a fuselink placed therein for conducting electricity between the top contact assembly and a bottom contact assembly. The bottom contact assembly has a bottom contact member which is capable of electrically coupled with the second electrical cable at one end thereof, and removeably coupled with the tube assembly at the other end thereof, such that a current path is formed from the second electrical cable to the tube assembly via the bottom contact member.

A HV HRC fuse, in particular a HH full-range fuse, for a drop-out fuse system with a drop-out release mechanism has an outer fuse housing, wherein at least one melting conductor, which is wound around at least one winding body, is provided in the fuse housing. The fuse housing is at least partially open on two end faces and a contact cap designed for electrical contacting is arranged on each end face of the fuse housing. The upper contact cap is detachably connectable in a contacting position with the drop-out release mechanism and the lower contact cap is pivotally mounted on the drop-out release mechanism. Tripping of the HV HRC fuse results in tripping of the drop-out release mechanism, whereby the upper contact cap is separated from the drop-out release mechanism and the HV HRC fuse swings out from the contacting position to a swing-out position.