The invention relates to a power tool (2), a kit of parts, and method of controlling the operation of the same depending upon the configuration of use of the power tool (2) at an instant of time. The power tool (2) can, in one embodiment be a router power tool to perform work on a workpiece (32), and switching means (28, 42) allow the selective operation of the power tool (2) by controlling an electrical power source. First switching means (28) include a no Voltage release (NVR) function and means are provided to selectively disable the NVR function of the first switching means (28) when the power tool (2) is used in at least one predetermined configuration. Typically, this allows second switching means (42) which include a NVR function to be used to control the power to the tool (2). A fence body for use with a router is also disclosed.

A motor protection device (1) that includes an interrupter unit (11, Q1, Q2) for electrically connecting a power supply (Vcc) and an electric motor (M) in an operation mode and electrically disconnecting the power supply (Vcc) and the electric motor in an alternative overload mode. The motor protection device further includes an overload detection unit (12) that is configured to monitor a motor current and to control the interrupter unit (11, Q1, Q2) to switch from the operation mode into the overload mode if the motor current indicates an overload condition of the electric motor (M) in the operation mode. The motor protection device (1) further includes a recovery detection unit (13) that is configured to monitor a motor temperature and to control the interrupter unit (11, Q1, Q2) to switch from the overload mode back into the operation mode if the motor temperature indicates a recovery from the overload condition.

A motor drive device includes a reactor, a converter circuit, a capacitor, an inverter circuit, and overcurrent determination units. The converter circuit converts a first AC voltage output from an AC power supply into a DC voltage. The capacitor smooths a second voltage on the DC side of the converter circuit. The inverter circuit converts DC power stored in the capacitor into AC power. One of the overcurrent determination units determines overcurrent based on a detected value of the first AC current, flowing between the AC power supply and the converter circuit. Another overcurrent determination unit determines overcurrent based on a detected value of the second DC current, flowing between the converter circuit and the capacitor. The converter and inverter circuits stop operating when the determination result of one of the overcurrent determination units indicates an overcurrent.

A method for detecting a short circuit in a winding of an electric motor being driven by a drive, the method includes measuring respective phase currents of the windings, transforming the phase currents to negative sequence components, and comparing the negative sequence components with respective baseline values. A corresponding control unit is further disclosed.

An electronic control device having multiple system circuits is such that power supply interrupting means is provided independently in all the system circuits, an abnormal system circuit is interrupted using the interrupting means in accordance with an abnormality being detected, and control is continued using a normal system circuit, whereby redundancy is improved. A multiple of system circuits formed of a drive unit system circuit and a controller system circuit are divided from a branch point of a power line, and furthermore, a relay function of being capable of controlling so as to interrupt a power supply to each system circuit is disposed in each system circuit, whereby each system circuit can independently be shut off or continue to be operated.

A motor management device controls the supply of electrical power to a motor by controlling at least one switching member. To be more easily adaptable, the device includes a platform and a modular connector which is separate from the platform. The platform bears an electronic unit including a power supply module controlling the switching member, a monitoring module intended to detect a fault of the motor, a protection module that disconnects the power supply in the event of a fault and a control module that controls the power supply module. The modular connector includes interchangeable connection elements, and includes at least as many connection elements of control output type as the device controls switching members, each connection element connecting a switching member to the power supply module, as well as a connection element of state output type connected to the monitoring module and providing an item of fault information when the monitoring module detects a fault of the electric motor.

A hybrid-electric powerplant (HEP) of an aircraft comprises a thermal engine providing a first torque input to the HEP and an electric motor providing a second torque input to the HEP. A power management system connected to one or both of the thermal engine and the electric motor comprises an engine control unit (ECU) connected to the thermal engine. The ECU controls fuel supplied to the thermal engine. An electric propulsion control (EPC) is connected to the electric motor and controls power supplied to the electric motor. The EPC includes an EPC protection module in communication with a power source for the electric motor. The EPC protection module disables power supplied to the electric motor upon receipt of a signal indicative of one or more of an over-speed condition and an over-torque condition detected in the HEP.

Disclosed herein is a liquid system tool having an integrated residual current device, RCD. The liquid system tool comprises a current circuit having a power input for receiving an alternating electrical current, AC, a rectifier for rectifying the AC into a direct current, DC, a voltage booster for increasing a DC voltage and a motor unit connected to an output of the voltage booster for driving the liquid system tool. The RCD comprises a sensor element connected to an output of the rectifier and an input of the voltage booster and being configured to collect an analog current signal and an analog to digital, A/D, converter configured to convert the analog current signal into a digital current signal. The integrated RCD further comprises a logic unit connected to the A/D converter, wherein the logic unit is configured to evaluate the digital current signal and compare it to a current requirement, and wherein if the logic unit determines that the digital current signal does not fulfill the current requirement, it is further configured to break the current circuit so that no current can flow in the liquid system tool. Also disclosed is a method for detecting residual current in a liquid system tool, and a computer program product.

A battery interrupter system including an electrical motor for a machine, at least one battery which powers an electrical system of a machine, a programable logic controller electrically connected to the electrical system and an ignition electrically connected to the programmable logic controller. The battery interrupter system also includes a button, which initiates the battery interrupter system, is connected to the programmable logic controller, at least one contactor electrically connected to the at least one battery and the programmable logic controller, wherein the programmable logic controller is configured to sends a signal to the at least one contactor to latch-in the contactor and enable an electrical connection between the at least one battery and the electrical system of the machine, and a detection sensor electrically connected to the programmable logic controller, wherein the detection sensor identifies operating conditions of the electrical system.

A bi-directional switch for an inductive machine is described. The bi-directional switch may include a first power semiconductor transistor with a first source, a first drain, and a first gate. The bi-directional switch may further include a second power semiconductor transistor with a second source, a second drain, and a second gate. The bi-directional switch may include the second source connected to the first source. The bi-directional switch may include a soft-starter device including a control circuit configurable to provide a first control signal to the first power semiconductor transistor and a second control signal to the second power semiconductor transistor.