A diagnostic method for solenoid valves includes detecting, at excitation of the solenoid, a variation rate of the supply voltage of the solenoid and comparing it with a predetermined value, generating an error signal if the variation rate is lower than the predetermined value, otherwise, detecting characteristics of the waveform of the solenoid current over a time interval between a moment of excitation of the solenoid and a moment wherein the movable core reaches end-stroke position, comparing the detected characteristics with threshold values, generating an alarm signal if the detected characteristics are lower than the threshold values, otherwise calculating the value of solenoid resistance and comparing it with a minimum resistance value and a maximum resistance value when the solenoid current is in steady state, and generating an alarm signal if the solenoid resistance value is lower than the minimum resistance value or greater than the maximum resistance value.

A switching device including: one or more fixed contacts and one or more movable contacts, each movable contact being reversibly movable between an opening position, at which the movable contact is decoupled from a corresponding fixed contact, and a closing position, at which the movable contact is coupled with the corresponding fixed contact; an electromagnetic actuator adapted to actuate the movable contacts between the opening and closing positions, the electromagnetic actuator including a fixed yoke and a movable armature operatively associated with the fixed yoke to form a magnetic circuit, the movable armature being reversibly movable between a first position, which corresponds to the opening position of the movable contacts, and a second position, which corresponds to the closing position of the movable contacts; and a kinematic chain to operatively connect the movable armature with the movable contacts, wherein the electromagnetic actuator includes a first excitation coil and a second excitation coil wound around the fixed yoke. The switching device further include a first power drive circuit adapted to provide a first excitation current to the first excitation coil and a second power drive circuit adapted to provide a second excitation current to the second excitation coil; the first and second power drive circuits are galvanically separated one from another and capable of operating independently one from another.

A system and a method for diagnosing a contactor life using contactor coil current, whereby, after a current value of a current contactor coil is determined based on a resistance value and a voltage value according to a real-time temperature of a contactor coil, whether contactor lifetime has expired and an abnormal operation thus occurs can be previously diagnosed and predicted on the basis of whether an average current value when a corresponding contactor operates a preset number of times or more exceeds a threshold value.

An object is to provide a new electronic control unit that can improve detection accuracy of a sense current even in a region where the current value of the sense current is small. Provided is a sense current detection unit including a plurality of sense transistors that have different current flow rates and that are connected to current output transistors controlling a current flowing in a coil load. The current in the sense current detection unit is input to an analog/digital converter, and the current value of the current flowing in the sense current detection unit is converted into a digital value. The current value of the current flowing in the sense current detection unit is increased through a combination or a selection of the plurality of sense transistors of the sense current detection unit in a region where the current value of the main current of the current output transistors is small compared to a region where the current value of the main current is large.

A bistable solenoid valve device for a fluid system includes a bistable solenoid valve and a detection device. The bistable solenoid valve has a permanent magnet yoke, an armature configured to be displaced between a first armature position for contact against a first core to form an air gap with a second core and a second armature position for contact against the second core to form an air gap with the first core. The bistable solenoid valve device further includes a detection device configured to evaluate and/or measure a first inductance of the first armature coil, and evaluate and/or measure a second inductance of the second armature coil without displacement of the armature, to compare the inductance of the first armature coil and the inductance of the second armature coil, and to output a state signal that indicates the armature position.

A method is provided for controlling an actuator comprising an electromagnet and a control device, the electromagnet including a coil and a moving part that moves between a first position and a second position, the control device including a power supply member configured to supply the coil with an electric current having a voltage and an amperage and a measurement member for measuring a value of a quantity from among the voltage and the amperage. The method includes acquiring samples of the measured value, of regulating, according to a proportional-integral-derivative algorithm, the electric current to around a setpoint value that is equal to a maintenance value capable of maintaining the moving part in the second position, of comparing each sample to a predetermined threshold and of detecting a movement of the moving part if a single sample is above or equal to the threshold.

Some embodiments provide irrigation valve control apparatuses comprising: a solenoid configured to cooperate with a plunger; an input stimulus source coupled with the solenoid and configured to apply an input stimulus while a plunger drive signal is not being applied and that is sufficiently small to not cause the plunger to move; sampling circuitry configured to measure one or more voltage measurements corresponding to one or more voltages across the solenoid, wherein the one or more voltage measurements are dependent upon the current position of the plunger relative to the solenoid; and control circuitry cooperated with the sampling circuitry to receive the one or more voltage measurements from the sampling circuitry, wherein the control circuitry is configured to determine whether the plunger is in one of the open and closed positions based on the one or more voltage measurements.

A controller of an electromagnetically driven reciprocating pump influences velocity of the magnetic armature by switching voltage applied to the electromagnet depending on the position of the magnetic armature, its position determined from state variables of the electromagnet. A processor calculates electrical resistance of the magnetic coil from the voltage and current measured by the measuring device, and calculates the temporal change of the linked magnetic flux in the electromagnet from the electrical voltage, the current and the resistance of the magnetic coil, and calculates the linked magnetic flux in the electromagnet from an earlier magnetic flux and from the temporal change, and determines the position of the magnetic armature from the linked magnetic flux in the electromagnet and the electrical current through the magnetic coil, and switches the voltage at the magnetic coil by the switching device depending on the position of the magnetic armature.

A method of controlling a solenoid valve having a solenoid coil and a poppet includes energizing a first node to a first voltage, and coupling the first node to the solenoid coil and energizing the solenoid coil using a pulse-width-modulated (PWM) signal having a frequency and a duty cycle configured to regulate a current conducted through the solenoid coil to below an opening threshold. The method further includes energizing a second node to a second voltage with energy stored in the solenoid coil, and coupling the second node to the solenoid coil and energizing the solenoid coil using a DC signal configured to increase the current to above the opening threshold. The method further includes coupling the first node to the solenoid coil and energizing the solenoid coil using the PWM signal having a frequency and duty cycle configured to regulate the current to above a closing threshold.

A method for controlling a part movable with a coil. In this case, a current flowing through the coil and/or a voltage applied to the coil is/are scanned in order to generate a coil signal. In a further step, at least one movement parameter representing an oscillatory movement of the part is ascertained by using the coil signal. Finally, at least one signal parameter of a dither signal is optionally changed to generate the oscillatory movement by comparing the movement parameter to the at least one setpoint value to adapt the oscillatory movement to the setpoint value.