A motor wiring member configured to supply three-phase alternating current to a motor includes conductive wires, each of which has a connecting portion being provided at one end and being configured to be connected to a coil end of a stator of the motor, a terminal being provided at an other end of each conductive wire and being configured to be connected to an electrode of a terminal block, and a surge suppression section being configured to suppress an overvoltage from being applied to the motor. The surge suppression section includes three series circuits, each of which includes a resistor and a capacitor. One ends of the three series circuits are electrically connected to the conductive wires of respective phases, and other ends of the three series circuits are electrically connected to each other. The surge suppression section is provided along with the conductor wires near the terminal and is located between the terminal and the connecting portion.

The invention relates to a circuit assembly for protecting a unit to be operated from a supply network against overvoltage, comprising an input having a first and a second input connection, which are connected to the supply network, an output having a first and a second output connection, to which the unit to be protected can be connected, and a protection circuit, which is provided between the first and the second input connections in order to limit the voltage present at the first and the second input connections. According to the invention, the protection circuit has a power semiconductor, in particular an IGBT, wherein a series circuit consisting of a diac, i.e., a bidirectional electrode, and a Zener element is connected between the collector and the gate of the power semiconductor, wherein the sum of the Zener voltage and the diac voltage results in a clamping voltage for the power semiconductor, which lies above the voltage of the supply network and defines the protection level.

An electronic barrier device, includes an Isolating Barrier or a Zener Barrier, with a voltage limiter or voltage shunt such as at least one zener device for voltage limitation in a circuit during a fault condition. The barrier device includes a crowbar device arranged to latch across the at least one voltage shunt device to reduce power dissipation in the at least one voltage shunt device in the circuit fault condition. The crowbar device is arranged to latch responsive to a change in a current flowing in the barrier device.

The invention relates to a space-saving isolating arrester, having for at least two electronic components (EB.sub.1, EB.sub.2) to be monitored, with the electronic components to be monitored being fastened to a carrier (P) using a thermally softenable fixing means, with an energy accumulator (D.sub.1,D.sub.2) being arranged on each of the electronic components which—when a thermally softenable fixing means softens—displaces the associated electronic component substantially parallel to the carrier (P), thereby disconnecting the associated electronic component, and also having a mechanically displaceable display means (ANZ), with the mechanically displaceable display means indicating that one or more of the electronic components to be monitored has been disconnected, and with the mechanically displaceable display means (ANZ) being displaced by a disconnecting electronic component.

An apparatus includes a surge protection device, a current sensor configured to sense a current through the surge protection device, and a surge discriminator circuit coupled to the current sensor and configured to discriminate among a plurality of surge levels for the surge protective device responsive to the sensed current. The current sensor may include a current transformer configured to generate a secondary current responsive to the sensed current and the surge discriminator circuit may be configured to discriminate among a plurality of surge levels responsive to the generated secondary current.

An electrostatic discharge (ESD) protection device includes: a first resistor coupled between a first input terminal of the ESD protection device and a first node of the ESD protection device; a second resistor coupled between the first node and a first output terminal of the ESD protection device; and a first ESD protection component coupled between the first node and a reference voltage terminal of the ESD protection device, where the reference voltage terminal is configured to be coupled to a reference voltage.

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.

The invention concerns a device for protection against transitory overvoltages, comprising: a varistor; a discharge tube; a thermofusible soldering securing a first electrode of the discharge tube and a first electrode of the varistor, the thermofusible soldering being a conductor of electricity and being able to melt beyond a temperature threshold when the varistor or the discharge tube heats up; the second electrode of the varistor being designed to be connected to a first electrical line and the second electrode of the discharge tube being designed to be connected to a second electrical line; a restoring element exerting a restoring force tending to move the first electrode of the varistor away from the first electrode of the discharge tube in order to allow a separation between the first electrode of the varistor and the first electrode of the discharge tube during a melting of the thermofusible soldering.

Disclosed in the present invention is a novel overvoltage protective device for lightning protection, comprising a first varistor, a second varistor, a PTC Thermistor, and lead-out terminals. The first varistor and the PTC Thermistor are connected in parallel, and then further connected in series with the second varistor to form a single port combined circuit. The surge-withstand capability of the first varistor is higher than the surge-withstand capability of the second varistor. At least one of the two lead-out terminals of the single port combined circuit is a thermally-conductive end with low thermal resistance. The second varistor is thermally coupled to the PTC Thermistor. The thermally-conductive end with low thermal resistance is thermally coupled to one or both of the second varistor and the PTC Thermistor.

A first surge absorber has a low resistance when a surge voltage which is greater than or equal to a first operating voltage is applied to a power supply line, and has a high resistance when the surge voltage which is greater than or equal to the first operating voltage is not applied. A detector outputs a detection signal indicating that the surge voltage is greater than or equal to the first operating voltage when the surge voltage is greater than or equal to the first operating voltage. A second surge absorber becomes a low resistance when a surge voltage greater than or equal to a second operating voltage is applied, and becomes a high resistance when a surge voltage greater than or equal to the second operating voltage is not applied.