A relay control circuit for use with a relay having a coil voltage input. The relay control circuit includes a first input to receive a first voltage capable of energizing the relay from a de-energized state, a second input to receive a second voltage, less than the first voltage, that is capable of maintaining the relay in an energized state, and means, responsive to a relay control signal having one of a first state and a second state, for switchably coupling the coil voltage input to the first input for a period of time sufficient to energize the relay in response to the relay control signal having the first state, and for switchably coupling the coil voltage input to the second input in response to expiration of the period of time.

A relay control circuit for use with a relay having a coil voltage input. The relay control circuit includes a first input to receive a first voltage capable of energizing the relay from a de-energized state, a second input to receive a second voltage, less than the first voltage, that is capable of maintaining the relay in an energized state, and means, responsive to a relay control signal having one of a first state and a second state, for switchably coupling the coil voltage input to the first input for a period of time sufficient to energize the relay in response to the relay control signal having the first state, and for switchably coupling the coil voltage input to the second input in response to expiration of the period of time.

A controllable trip device includes a magnetic actuator, including a coupling member intended to be coupled to a switching mechanism of an electrical circuit breaker to cause the switching thereof and a coil configured to displace the coupling member towards a tripped position when it is supplied with a pulse of a current of intensity greater than a first predefined threshold for a duration greater than or equal to a predefined duration, a control device, configured to supply the coil, immediately on receipt of a control signal, with a series of pulses of duration equal to the predefined duration and of intensity greater than or equal to the first threshold and less than or equal to a second threshold equal at most to 120% of the first threshold.

A controllable trip device includes a magnetic actuator, including a coupling member intended to be coupled to a switching mechanism of an electrical circuit breaker to cause the switching thereof and a coil configured to displace the coupling member towards a tripped position when it is supplied with a pulse of a current of intensity greater than a first predefined threshold for a duration greater than or equal to a predefined duration, a control device, configured to supply the coil, immediately on receipt of a control signal, with a series of pulses of duration equal to the predefined duration and of intensity greater than or equal to the first threshold and less than or equal to a second threshold equal at most to 120% of the first threshold.

A solenoid coil discharging circuit includes a rectifier, transistor, and diode. The rectifier is coupled to an alternating current signal, and provides a rectified signal in response to being coupled to the alternating current signal. The transistor is coupled to the rectifier circuit, and biased in on in response to the alternating current signal being coupled to the rectifier, thereby enabling coupling of the rectified signal to a solenoid coil. The diode is coupled to the rectifier, and discharges current from the solenoid coil in response to the alternating current signal being de-coupled from the rectifier. A method of discharging a solenoid coil includes rectifying an alternating current signal to provide a rectified signal, biasing a transistor on in response to the alternating current signal being rectified, thereby enabling coupling of the rectified signal to the solenoid coil through the transistor, and discharging current from the solenoid coil through the diode in response to discontinuing rectification of the alternating current signal.

A low-side contactor coil drive circuit can include an input line and a first solid state switch having a first switch base, a first switch collector, and a first switch emitter. The first switch collector can be connected to the input line and the first switch emitter is connected to ground. The circuit can include a second solid state switch having a second switch base, a second switch collector, and a second switch emitter. The second switch emitter can be connected to the input line in parallel with the first switch collector. The second switch collector can be connected to the first switch base. The circuit can include a third solid state switch having a third switch gate, a third switch source, and a third switch drain. The third switch drain can be connected to the second switch base.

The invention relates to a method for determining a characteristic value of a magnetic switch valve. The magnetic switch valve can be switched from a closed switch state into an open switch state, via the movement of a rotor by means of a switching magnet applied with current against a conservative restoring force. According to the invention, during the switching of the switch valve from the open state into the closed state, the time course of the current flowing through the switching magnet and/or of the voltage at the switching magnet is measured. The characteristic value to be measured is evaluated from this time course. It was recognized that every movement of the rotor against the switching magnet induced a voltage in same. Now the voltage at the switching magnet is regulated at a constant value, for one, the voltage induced by the movement can be observed as a control deviation in the short term. For another, the induced voltage causes a current flow through the switching magnets. Based on this, the kinematics of the rotor can be deduced. Given that the switching magnet has an ohmic resistance, energy is also dissipated via the current flow. This energy is the key to determining the switching path covered by the rotor when switching between the closed and the open state. The invention also relates to a measuring device that is particularly suitable for the method.

One embodiment describes a tangible, non-transitory, computer-readable medium storing instructions executable by a processor of an operating coil driver circuitry. The instructions include instructions to instruct a switch to supply a specific current to an operating coil of a switching device using a pulse-width modulated signal; determine duty cycle of the pulse-width modulated signal; and determine wellness of the switching device based at least in part on the duty cycle of the pulse-width module signal.

A relay control circuit for use with a relay having a coil voltage input. The relay control circuit includes a first input to receive a first voltage capable of energizing the relay, a second input to receive a second voltage, less than the first voltage, that is capable of maintaining the relay in an energized state, and means, responsive to a relay control signal having one of a first state and a second state, for switchably coupling the coil voltage input to the first input in response to the relay control signal having the first state, and for switchably coupling the coil voltage input to the second input in response to the relay control signal having the second state.

A relay control circuit for use with a relay having a coil voltage input. The relay control circuit includes a first input to receive a first voltage capable of energizing the relay, a second input to receive a second voltage, less than the first voltage, that is capable of maintaining the relay in an energized state, and means, responsive to a relay control signal having one of a first state and a second state, for switchably coupling the coil voltage input to the first input in response to the relay control signal having the first state, and for switchably coupling the coil voltage input to the second input in response to the relay control signal having the second state.