A disconnector device including an isolator connected between a first terminal and to a second terminal, and a sleeve positioned around the isolator and moveable between an un-extended position prior to the isolator operating and an extended position after the isolator operates, the sleeve being configured to trap debris produced by operation of the isolator.

A power management system includes a first power line, a second power line, a first parallel protector, a second parallel protector, a third parallel protector, a first current sensor, a second current sensor, a third current sensor, and a processor. The first parallel protector is coupled to the first power line. The second parallel protector is coupled to the first parallel protector and the second power line. The third parallel protector is coupled to the first parallel protector and a ground terminal. The first current sensor, the second current sensor and the third current sensor respectively sense a first current flowing through the first parallel protector, a second current flowing through the second parallel protector, and a third current flowing through the third parallel protector. The processor detects a surge discharging path according to the first current, the second current and/or the third current.

A power source control device that includes: a make-and-break relay configured to either make or break conduction between a first terminal of a load and a first electrode of a direct current power source; a dark current generation circuit configured to generate a dark current by lowering a voltage of the direct current power source, in a state in which a first terminal is connected to the first electrode of the direct current power source and a second terminal is connected to the first terminal of the load so as to be parallel to the make-and-break relay; and a bypass circuit configured to dissipate some of power supplied from an external charger by making conduction between a second electrode of the direct current power source and the first terminal of the load in response to the direct current power source being charged by the external charger.

A lighting relay panel may include lower-cost features or components related to improved safety and reliability. In some cases, the relay panel includes a power supply capable of protecting the panel from high-voltage and high-current transients. A microcontroller may determine a power interruption based on a zero-cross signal received from the power supply, and may also configure latching relays during the interruption. In some implementations, the relay panel includes a relay sense circuit that is capable of receiving actuation signals from multiple relays connected to different phases of a power signal, and the microcontroller may synchronize or repeat the actuations based on a signal from the relay sense circuit. The microcontroller may generate relay addresses based on the relay positions within the relay panel. In some cases, the relay panel may include isolation circuits that are capable of providing an isolated control signal having an improved voltage range.

Aspects of this disclosure relate to detecting and recording information associated with electrical overstress (EOS) events, such as electrostatic discharge (ESD) events. For example, in one embodiment, an apparatus includes an electrical overstress protection device, a detection circuit configured to detect an occurrence of the EOS event, and a memory configured to store information indicative of the EOS event.

A circuit arrangement for a surge protection device for protecting multiple DC or AC power lines. The circuit arrangement includes a plurality of DC or AC power line inputs, a negative potential or neutral input, a ground potential input, a surge protection component having one or more surge elements, a rectification circuit including a plurality of diodes, and an alarm circuit for receiving a status output from the surge protection component.

A drive for a mobile compressor includes EMI and transient protection circuits, second chokes, converters and an inverter. The EMI and transient protection circuits include respectively common mode chokes and at least one component. Each of the common mode chokes is configured to receive a first direct current voltage and is connected to first and second grounds. The at least one component is connected to a third ground. The first, second and third grounds are at different voltage potentials. The second chokes are connected downstream from the common mode chokes. The converters are connected to outputs of the second chokes and are configured to collectively provide a second direct current voltage to a direct current bus. The inverter is connected to the direct current bus and configured to convert the second direct current voltage to an alternating current voltage to power the mobile compressor downstream from the inverter.

A lighting relay panel may include lower-cost features or components related to improved safety and reliability. In some cases, the relay panel includes a power supply capable of protecting the panel from high-voltage and high-current transients. A microcontroller may determine a power interruption based on a zero-cross signal received from the power supply, and may also configure latching relays during the interruption. In some implementations, the relay panel includes a relay sense circuit that is capable of receiving actuation signals from multiple relays connected to different phases of a power signal, and the microcontroller may synchronize or repeat the actuations based on a signal from the relay sense circuit. The microcontroller may generate relay addresses based on the relay positions within the relay panel. In some cases, the relay panel may include isolation circuits that are capable of providing an isolated control signal having an improved voltage range.

A circuit protection device includes a temperature sensitive resistor element, a dielectric layer, a first electrically insulating layer, a first electrode and a second electrode. The temperature sensitive resistor element has a first electrically conductive layer, a second electrically conductive layer and a positive temperature coefficient (PTC) layer disposed therebetween. The first electrically conductive layer has two electrically conductive blocks. The two electrically conductive blocks dispose on the surface of the PTC layer, thus forming a trench in the PTC layer. The dielectric layer is disposed in the trench. The first electrically insulating layer is disposed on the first electrically conductive layer and covers the dielectric layer. The first and second electrodes are disposed on the first electrically insulating layer, and electrically connected to the two electrically conductive blocks, respectively.

A three-stage surge protection device protects against complex, time-variant voltage transients, including those resulting from a high-altitude nuclear electromagnetic pulse or a solar coronal mass ejection. The device relies on interaction between a snubbing low-pass filter, a transient voltage suppressor, and an electronic crowbar circuit. The low-pass filter significantly lowers the let-through voltage of the device for short-duration pulses, and helps to spread the energy to more effectively utilize the transient voltage suppressor. The transient voltage suppressor limits the let-through voltage to a clamping level and provides indication to the crowbar circuit when it is no longer able to do so. Once the clamping level is no longer able to be maintained, the crowbar circuit draws enough current to trip an upstream protective device, such as a breaker or fuse.