Abstract: An arrangement in which a valve assembly is provided between the supply air inlet and the magnetic valve that is activated by a position threshold sensor that can be activated by the actuator element and/or a pressure threshold sensor registering the actuating pressure on the magnetic valve and connects the magnetic valve directly to the supply air to increase the availability of the actuator device when the position threshold sensor detects the attaining of a specified operation position of the actuator element or the pressure threshold sensor detects the failure to attain a specified minimum pressure.

Abstract: A control device with a valve adjusted by a control element is provided. A position sensor detects an actual position of the control element and an electro-pneumatic position controller generates a pneumatic control variable as a function of the actual and desired positions. The pneumatic control variable is supplied to the control drive via a magnetic valve activated by a supply voltage supplied by an instrumentation and control device. For carrying out a test of the magnetic valve, the magnetic valve is deactivated briefly. To initiate, monitor, and evaluate the test of the magnetic valve, the supply voltage is supplied to the magnetic valve via a controllable switch. The controllable switch is opened by a magnetic valve test signal generated by the instrumentation and control device. The magnetic valve test signal is supplied to the controllable switch via a limit switch which is opened when the control element reaches a specified position.

Abstract: An actuating device for an on/off valve having a pneumatic drive that is connected to a compressed air supply by a solenoid valve, wherein when driven with a control voltage, the solenoid valve ventilates the pneumatic drive with the compressed air and, when the control voltage is not present, vents the pneumatic drive. The pneumatic drive moves the on/off valve into an operating position during ventilation and moves it into a safety position during venting. To permit the performance of partial-stroke tests in the simplest way possible, a device for performing the partial-stroke test includes a controllable switch which is closed in a quiescent state, and in this case supplies the control voltage to the solenoid valve. The controllable switch is opened by a control signal that is generated to perform the partial-stroke test.

Abstract: An arrangement in which a valve assembly is provided between the supply air inlet and the magnetic valve that is activated by a position threshold sensor that can be activated by the actuator element and/or a pressure threshold sensor registering the actuating pressure on the magnetic valve and connects the magnetic valve directly to the supply air to increase the availability of the actuator device when the position threshold sensor detects the attaining of a specified operation position of the actuator element or the pressure threshold sensor detects the failure to attain a specified minimum pressure.

Abstract: A control device with a valve adjusted by a control element is provided. A position sensor detects an actual position of the control element and an electro-pneumatic position controller generates a pneumatic control variable as a function of the actual and desired positions. The pneumatic control variable is supplied to the control drive via a magnetic valve activated by a supply voltage supplied by an instrumentation and control device. For carrying out a test of the magnetic valve, the magnetic valve is deactivated briefly. To initiate, monitor, and evaluate the test of the magnetic valve, the supply voltage is supplied to the magnetic valve via a controllable switch. The controllable switch is opened by a magnetic valve test signal generated by the instrumentation and control device. The magnetic valve test signal is supplied to the controllable switch via a limit switch which is opened when the control element reaches a specified position.

Abstract: An actuating device for an on/off valve having a pneumatic drive that is connected to a compressed air supply by a solenoid valve, wherein when driven with a control voltage, the solenoid valve ventilates the pneumatic drive with the compressed air and, when the control voltage is not present, vents the pneumatic drive. The pneumatic drive moves the on/off valve into an operating position during ventilation and moves it into a safety position during venting. To permit the performance of partial-stroke tests in the simplest way possible, a device for performing the partial-stroke test includes a controllable switch which is closed in a quiescent state, and in this case supplies the control voltage to the solenoid valve. The controllable switch is opened by a control signal that is generated to perform the partial-stroke test.

Abstract: An adjustment device for an open-close valve (1) has a pneumatic drive (2) which is aerated or de-aerated according to the presence or absence of a control voltage (Vs) which can be supplied by a control system (5). The valve (1) moves into an operating position when the drive is aerated, and into a safety position when the drive is de-aerated. The valve (1) is provided with an electro-pneumatic position regulator (8) for carrying out a partial stroke test.

Abstract: The invention relates to a method for monitoring a pipeline in order to detect the slow reduction of the free inner cross-section by means of the position of a control valve in the pipeline. When the flow rate is essentially constant, a first position is determined and stored at a first moment. According to at least one second position of the control valve, determined at a second, subsequent moment, the point at which the position of the valve exceeds a pre-deterrninable threshold value for a valve opening is determined, and optionally a signal is emitted to indicate that the threshold value has been exceeded and/or the time at which it was exceeded. As a result, suitable maintenance measures can be introduced, before faults occur in the process system.

Abstract: The invention relates to a method for monitoring a pipeline in order to detect the slow reduction of the free inner cross-section by means of the position of a control valve in the pipeline. When the flow rate is essentially constant, a first position is determined and stored at a first moment. According to at least one second position of the control valve, determined at a second, subsequent moment, the point at which the position of the valve exceeds a pre-determinable threshold value for a valve opening is determined, and optionally a signal is emitted to indicate that the threshold value has been exceeded and/or the time at which it was exceeded. As a result, suitable maintenance measures can be introduced, before faults occur in the process system.