A system includes a latch circuit configured to monitor a switch and to operate an electronic latch based on a position of the switch. The system also includes a power supply circuit configured to provide a first voltage level to the latch circuit during normal operations and a second voltage level to the latch circuit during power loss. The power supply circuit includes a primary power circuit configured to provide the first voltage level to the latch circuit and a plurality of supercapacitors configured to be charged by the primary power circuit and provide the second voltage level to the latch circuit.

Device for the command and control of the electric power supply of one or more windings of an electromagnetic actuator, comprising a plurality of electronic means configured to receive at the input either a direct current feeding voltage or alternatively an alternating current feeding voltage and to generate at the output a first digital command signal suitable for triggering an activation phase of the electromagnetic actuator in which at least one the one or more windings is powered, for a first predefined and adjustable time interval, with an activation current, a second digital command signal suitable for triggering a maintenance phase of the electromagnetic actuator in which the one or more windings are powered with a maintenance current having an intensity lower than the activation current, and a third digital command signal suitable for triggering a third phase of deactivation of the electromagnetic actuator in which the power supply of the one or more windings is interrupted for a second predefined and adjustable time interval.

In an example, a system for applying an agricultural product includes a valve and a solenoid. For instance, the valve includes a coil that generates a magnetic flux. The system includes a valve controller. The valve controller is configured to measure one or more electrical characteristics of at least one of the coil or a dissipation element. In some examples, the valve controller determines an actual duty cycle of a valve operator of the valve using the measured electrical characteristics. The valve controller determines a magnetic flux correction, for instance based on a difference between the actual duty cycle and a specified duty cycle. The valve controller operates the valve operator according to the specified magnetic flux and the magnetic flux correction to guide the actual duty cycle toward the specified duty cycle.

The present invention relates to a method for providing watering or non-watering of a specific area of soil through a first plurality of irrigation valves (42). Specific irrigation parameters are measured at the specific area of soil through a second plurality of field sensors (54). A controller unit (30) is interconnected to a third plurality of control units (18). Each control unit is connected to a specific irrigation valve and/or a specific field sensor. A type declaration providing communication under a second communication protocol is transmitted from the controller unit to the third plurality of control units using a first communications protocol. A second set of instructions are transmitted from the controller unit to the third plurality of control units using a second communications protocol. A first set of instructions are transmitted from the controller unit to the third plurality of control units using the first communications protocol.

A contactor for medium voltage electric systems including: one or more electric poles; for each electric pole, a fixed contact and a corresponding movable contact reversibly movable between a first position, at which the movable contact is decoupled from the fixed contact, and a second position, at which the movable contact is coupled with the fixed contact; an electromagnetic actuator including a magnetic yoke having a fixed yoke member and a movable yoke member, the movable yoke member reversibly movable between a third position corresponding to the first position of the movable contacts, at which the movable yoke member is decoupled from the fixed yoke member, and a fourth position, corresponding to the second position of the movable contacts, at which the movable yoke member is coupled with the fixed yoke member, the electromagnetic actuator including an excitation circuit assembly including an excitation coil wound around the magnetic yoke and electrically connected with an auxiliary electric power supply to be fed with an excitation current to generate an excitation magnetic flux to move the movable yoke member from the third position to the fourth position or to maintain the movable yoke member in the fourth position; an opening springs operatively coupled with the movable yoke member to move the movable yoke member from the fourth position to the third position; a kinematic chain to operatively connect said movable yoke member with said movable contacts. The electromagnetic actuator including camping circuit assembly comprising a damping coil arranged to form a conductive loop adapted to be at least partially enchained with the excitation magnetic flux generated by the excitation current flowing along the excitation coil, when the auxiliary electric power supply provides the excitation current to the excitation coil, so that a secondary current circulates along the damping coil when the excitation magnetic flux is subject to a transient.

There is provided a method of energising a solenoid of a valve assembly, comprising the steps of applying a positive over boost voltage to the solenoid to actuate a moveable plunger to open or close a flow path through the valve assembly, and then applying a negative braking voltage to brake the movement of the plunger during movement of the moveable plunger. There is also provided a method of energising a solenoid of a valve assembly, the method comprising the steps of receiving a demand signal to actuate the valve, applying a wait time after receipt of the demand signal, applying a positive over boost voltage across the solenoid to actuate a moveable plunger to open or close a flow path through the valve assembly, monitoring the solenoid closure time, and adjusting one or more input variables in order to control the solenoid closure time. There is also provided a method of monitoring the solenoid closure time over a plurality of different energising and de-energising cycles of the solenoid and generating an output to indicate a need for valve maintenance. Finally, there is provided a controller and a valve assembly configured to perform these methods.

A method checks the plausibility of a measurement of an actuator current by use of an actuator two-terminal network. The actuator two-terminal network contains an inductive load and a resistive load. A first pole of the actuator two-terminal network is connected to a supply voltage via a pulse-width-modulated switch and is connected to earth via a freewheeling diode arranged in the reverse direction, and wherein a second pole of the actuator two-terminal network is connected to earth.

Techniques for diagnosing failures in a digital solenoid I/P converter are provided herein. A controller of the I/P converter may apply a fixed voltage to the I/P converter, causing an armature to move from an off-position to an on-position in a properly-functioning I/P converter. The controller may receive an indication of whether a digital logic line trip has occurred, indicating that a current for the I/P coil has reached a desired maximum current level, and an elapsed time from the application of the fixed voltage. The controller may compare the amount of time elapsed from the application of the fixed voltage to an expected amount of elapsed time from the application of the fixed voltage to the I/P coil after which a digital logic line trip will occur for a properly functioning I/P coil and diagnose, based on the comparison, a failure in the I/P converter.

A sprayer control system includes a plurality of smart nozzles each having at least one control valve with a valve operator, an electronic control unit for the valve operator, and one or more spray nozzles. The at least one control valve and the ECU control a flow rate of liquid agricultural product through the nozzles. A duty cycle modulator is in communication with the ECU and generates an applied duty cycle for the at least one control valve. The duty cycle modulator includes a specified duty cycle input having a specified duty cycle and a pressure monitor associated with the at least one control valve. A pressure comparator compares the valve pressure determined with the pressure monitor with a system pressure and generates a pressure error. An applied duty cycle generator generates the applied duty cycle based on the specified duty cycle modified by the pressure error.

A controller for a linear solenoid valve is configured to: calculate an average value of an exciting current within a period including a natural number multiple of the dither cycle as an average current value; execute a feedback control on a control value of the pulse width modulation signal such that a target value of the exciting current and the average current value match; and calculate a dither correction amount by multiplying a ratio between the control value of the pulse width modulation signal obtained by the feedback control and the average current value by a dither current value that is a current value corresponding to the dither correction amount and calculating the dither correction amount such that an increase in the exciting current due to the dither correction amount is canceled out by a decrease in the exciting current due to the dither correction amount within one dither cycle.