A fieldbus solenoid valve system has a solenoid operated control valve mounted and operated by a solenoid pilot. A direct current power source is connected to a coil of the solenoid pilot and a driver for actuating the coil. A resistive element is in series with the power source, the driver, the solenoid and a ground. A frequency generator is connected to the circuit for creating a frequency pulse train to the coil having a characterization so as not to cause the solenoid pilot to actuate. The voltage is measured between the coil and resistive element and the measured voltage is compared to a base voltage value measured from the same circuit location. An indicator signal is displayed on the fieldbus solenoid valve system or externally when the measured voltage increases to a predetermined amount from said base voltage over time.

A system and method for detecting faults and optimiz-ing power usage of solenoid valves. The method includes obtaining a current signature of the solenoid coil, using a dedicated circuit to detect various features and using a pulse width modulation controller optimize the power output of the system. Additionally, using machine learning, the system can be optimized using data from the dedicated circuit.

The present invention relates to a device for detecting leaks in a hydraulic cylinder, comprising: a first pressure sensor for detecting a pressure value in a first pressure chamber of a hydraulic cylinder, a second pressure sensor for detecting a pressure value in a second pressure chamber of the hydraulic cylinder, an evaluation unit for continuously detecting the pressure values of the first pressure sensor and the second pressure sensor, the evaluation unit being designed to detect a leak, preferably an internal leak, in the hydraulic cylinder that deviates from the norm based on the pressure values recorded by the first pressure sensor and the second pressure sensor.

The disclosure provides a method for testing a solenoid valve for triggering a safety valve having a single-acting fluidic drive and a positioner. The drive fluid pressure is increased by a first pressure difference. An attempt is made to switch the solenoid valve to the safety position. The drive fluid pressure is measured at a specified point in time that is selected such that the pressure in the drive fluid lowers at most by the first pressure difference. If the pressure in the drive fluid is higher than a reference pressure at the specified point in time, the functionality test of the solenoid valve is failed. The lowering of the pressure in the drive fluid is monitored over a defined period of time to make conclusions regarding the pressure generating system. The pressure does not fall below the operating pressure so the position of the valve member remains constant.

A process valve apparatus (10), including: a process fitting (1) with a valve member (2), a pneumatic valve drive (3) for actuating the valve member (2), and a control device (4) with a pneumatic valve device (5) for pneumatically actuating the valve drive (3), wherein the control device (4) is configured to carry out a partial stroke test and, within the partial stroke test: to actuate the valve drive (3) pneumatically by means of the valve device (5), so that the valve drive (3) sets the valve member (2) in a test movement sequence in which the valve member (2) performs a first test movement from a first position (x1) to a second position (x2) and a second test movement from the second position (x2) back to the first position (x1), to detect pressure information related to the pneumatic actuation of the valve drive (3) and, taking into account the pressure information, to determine status information indicating the functioning and/or the wear of the process valve apparatus (10).

There is provided an hydraulic actuation system for an aircraft, the hydraulic actuation system includes an actuator (A), a primary actuation arrangement to provide hydraulic fluid to control the actuator (A), wherein the hydraulic actuation system is configured to detect a fault in the actuator (A). The hydraulic actuation system also includes a secondary actuation arrangement to provide hydraulic fluid to control the actuator (A) in response to a detection of a fault in the actuator (A).

An aircraft pneumatic system including a pneumatic actuator arranged to operate at a pressure value at least equal to a pressure threshold, a line fluidly connected between a pneumatic source and the pneumatic actuator, and a venturi disposed upstream of the line and downstream of the pneumatic source. The venturi is configured to receive a source flow from the source at a mass flow rate, the mass flow rate being between a lower, nominal flow rate value and a higher, graded flow rate value. The venturi is sized such that when the mass flow rate is at the nominal flow rate value, a line pressure inside the line corresponds to a source pressure upstream of the venturi, and when the mass flow rate to the venturi is at the graded flow rate value, the line pressure is less than the source pressure.

A failure detection apparatus for a hydraulic system, to a hydraulic, failure detection-capable system, and to a method of operating a failure detection apparatus. The failure detection apparatus comprises a monitoring and failure detection unit that receives first and second pressure values from first and second pressure sensors and comprises a failure detection unit that detects a failure of at least one hydraulically operated device when a 2-tuple of a plurality of 2-tuples is within a first and outside a second predetermined tolerance range of relative pressure values, and wherein the failure detection unit 260 detects a failure of the pump when a 2-tuple of the plurality of 2-tuples is outside the first predetermined tolerance range of relative pressure values.

A spring return hydraulic or pneumatic valve is actuated, by an actuator, from a first position to a second position. A displacement of the valve is measured. A hydraulic or pneumatic pressure of the valve actuator is measured. A spring constant of the spring is calculated based on the measured displacement and the measured pressure. The calculated spring constant is compared with a manufacturer listed spring constant.

An actuator system includes a piston-cylinder arrangement including a piston that is movable with respect to a cylinder. A first flow path is in fluid communication with the piston-cylinder arrangement and a second flow path is in fluid communication with the piston-cylinder arrangement. A control system is operable to fluidly connect the first flow path to a source of high-pressure fluid and to connect the second flow path to a drain to move the piston in a first direction. A pressure sensor is fluidly connected to the first flow path and is operable to measure sufficient pressure data during the movement of the piston to generate a pressure versus time curve. The control system is operable to compare the generated pressure versus time curve to a known standard pressure versus time curve stored in the control system to determine the condition of the piston-cylinder arrangement.