Abstract: The invention relates to a positioner (10) for an actuator (12) comprising a processing unit (22) and an output unit (20) which can be connected to an actuating drive (15) of an actuator (12), as well as a measurement unit (24). The invention is characterized in that said positioner (10) comprises a current source (26) which can be connected to a voltage source (30) of a control system (14) via a single two-wire current loop (28). The invention furthermore relates to a method for operating a positioner (10) including the transmission of measuring values recorded in the positioner (10) to a higher-level controller (14). The method is characterized in that the actuating signals are transmitted in a digital form whereas the measuring data is transmitted to a higher-level controller in an analog form, with both digital and analog signals being transmitted on the same two-wire line.

Abstract: In a pneumatic actuator for setting a control armature, a first working chamber and a second working chamber are pneumatically separated from each other by a moveable dividing wall to which the control armature is coupled in a force-transmitting manner. The dividing wall, in case of a pressure difference between the working chambers, is displaced in a first control direction. A positioner is adapted to output at least one pneumatic control signal to the first working chamber. The first and the second working chambers are pneumatically connected to each other via a pneumatic short-circuit duct with a balancing valve disposed in the short-circuit duct for at least one of closing or opening the short-circuit duct. The balancing valve is driveable by the positioner such that in case of a certain operating condition, the balancing valve pneumatically short-circuits the first and the second working chamber for achieving a pressure balance between the chambers.

Abstract: In a limit signal indicator for determining two positions of a pneumatically operated positioning device, a position sensor detects a position of the positioning device. A first signal transmission contact, a second signal transmission contact, and a microprocessor are provided. The first and the second signal transmission contacts each output a respective electrical limit position signal, the limit position signals representing an adoption of the first and the second positions or of at least one position of the positioning device above or below a predetermined set limit value. At least one of the signal transmission contacts is connected for signal transmission so that in case of a malfunctioning of a signal transmission, the switch amplifier is capable of generating an emergency signal above a maximum limit value or below a lower limit value, and to transmit the emergency signal to an external processing location.

Abstract: The invention relates to a positioner (10) for an actuator (12) comprising a processing unit (22) and an output unit (20) which can be connected to an actuating drive (15) of an actuator (12), as well as a measurement unit (24). The invention is characterized in that said positioner (10) comprises a current source (26) which can be connected to a voltage source (30) of a control system (14) via a single two-wire current loop (28). The invention furthermore relates to a method for operating a positioner (10) including the transmission of measuring values recorded in the positioner (10) to a higher-level controller (14). The method is characterized in that the actuating signals are transmitted in a digital form whereas the measuring data is transmitted to a higher-level controller in an analog form, with both digital and analog signals being transmitted on the same two-wire line.

Abstract: The invention relates to an actuator (10) for controlling a fluid flow comprising a basic housing (12a) having an inlet (14) and an outlet (16), a valve seat (18) provided in the basic housing (12) between said inlet and said outlet (14, 16), a valve body (20) that can be operatively connected to the valve seat (18), a valve rod (22) for actuating said valve body (20) as well as means for actuating the valve rod (22). The invention is characterized in that an additional housing (12b) is mounted on said basic housing (12a) in a fluid tight manner and that the basic and additional housings (12a, 12b)—with the exception of the inlet and outlet (14, 16) form a completely sealed housing (12) that is closed on all sides and only includes one circumferential seal (24), and that said valve rod (22) is completely disposed inside said sealed housing (12) without any passage.

Abstract: The invention relates to an actuator (10) for controlling a fluid flow comprising a basic housing (12a) having an inlet (14) and an outlet (16), a valve seat (18) provided in the basic housing (12a) between said inlet and said outlet (14,16), a valve body (20) that can be operatively connected to the valve seat (18), a valve rod (22) for actuating said valve body (20) as well as means for actuating the valve rod (22) The invention is characterized in that an additional housing (12b) is mounted on said basic housing (12a) in a fluid tight manner and the means for actuating the valve rod is disposed within the housing(12) formed by the basic and additional housings (12a, 12b).

Abstract: In a pneumatic actuator for setting a control armature, a first working chamber and a second working chamber are pneumatically separated from each other by a moveable dividing wall to which the control armature is coupled in a force-transmitting manner. The dividing wall, in case of a pressure difference between the working chambers, is displaced in a first control direction. A positioner is adapted to output at least one pneumatic control signal to the first working chamber. The first and the second working chambers are pneumatically connected to each other via a pneumatic short-circuit duct with a balancing valve disposed in the short-circuit duct for at least one of closing or opening the short-circuit duct. The balancing valve is driveable by the positioner such that in case of a certain operating condition, the balancing valve pneumatically short-circuits the first and the second working chamber for achieving a pressure balance between the chambers.

Abstract: The invention relates to a process control system having measuring devices and actuators. All of the measuring devices and actuators process information and exchange data amongst themselves. All measuring devices and actuators are interconnected to enable a bi-directional data exchange. Several, or all of the measuring devices and actuators can exchange data with a service unit that can be connected to the devices and actuators. The invention also relates to a method for operating a process control system of this type.

Abstract: Both improved protection against explosions and the possibility of performing diagnoses even when the I/P converter has been disconnected are to be provided by a position controller (5) for a pressure medium-operated actuating system, the controller being designed to be connected by a pneumatic line to a pneumatic drive (4)-equipped actuator (1) of an actuating element, especially an actuating element of a safety valve (2), where the actuator (1) has an electric power line (6) for controlling an I/P converter (7) according to the live-zero principle, and where the I/P converter (7) can be driven by an electrically controlled switch (10). The goal is achieved in that the switch (10) is designed to be driven by an additional circuit (11), which is connected to the power line (6) and installed in the position controller and which monitors the current in the power line (6).

Abstract: In a limit signal indicator for determining two positions of a pneumatically operated positioning device, a position sensor detects a position of the positioning device. A first signal transmission contact, a second signal transmission contact, and a microprocessor are provided. The first and the second signal transmission contacts each output a respective electrical limit position signal, the limit position signals representing an adoption of the first and the second positions or of at least one position of the positioning device above or below a predetermined set limit value. At least one of the signal transmission contacts is connected for signal transmission so that in case of a malfunctioning of a signal transmission, the switch amplifier is capable of generating an emergency signal above a maximum limit value or below a lower limit value, and to transmit the emergency signal to an external processing location.

Abstract: In a method or device for function-monitoring an actuator in a process engineering plant, said actuator comprising a valve and an actuating drive for actuating said valve. A positioner is provided for setting a position of the valve, the positioner comprising a controller module. A predefined activation test signal is generated and applied to the controller module to position the actuator into a predefined function condition. A control signal is generated by the controller module for signalling the actuating drive in accordance with the activation test signal and an output control signal is sensed and monitored as compared to a reference control signal.

Abstract: In a system or method for setting a positioning member, a pneumatic positioning drive actuates the positioning member, the pneumatic positioning drive having at least two control positions and a predetermined safety position. A position controller is pneumatically coupled to the positioning drive. A basic process control system generates and transmits a set-point signal for the positioning member. A safety controller generates and transmits a safety signal with which the pneumatic positioning drive is vented causing the positioning member to automatically move into the predetermined safety position. The basic process control system and the safety controller are coupled with respect to signal transmission in such a way that the set-point signal generated by the basic process control system is transmitted via the safety controller and a signal transmission path coupling the position controller with the safety controller.

Abstract: In a method or system for function testing of a safety valve in engineering plant, it is tested whether the safety valve travels from a normal position to a predetermined final position in a certain operating situation of the plant. A bypass the valve bypasses the safety valve and assumes an idle position in a normal operation of the plant and a predetermined test position for function testing of the safety valve. The test position of the bypass valve is established such that a predetermined fluid flow through the bypass valve is permitted.

Abstract: In a positioner for a double-acting pneumatic actuator having first and second pneumatically loadable working chambers as well as a movable working part which is shiftable for an actuating movement at a pressure difference in the first and second working chambers, the positioner comprises first and second pneumatic control signals output to the first and second working chambers, respectively. At least one adjusting device for adjusting the first pneumatic control signal for the first working chamber is provided. The adjusting device is designed such that the adjustment of the first control signal according to a control leaves the second control signal unaffected. In a method for operating the double-acting pneumatic actuator, an average pressure value of the first and the second working chambers is determined in a fully regulated state of the actuator.

Abstract: The invention pertains to a method for verifying the performance of a test of the functionality of an actuator (1) with a drive (2) and a valve (3a), where the valve (3a) can be moved by the drive (2), which uses a drive element (3) acting on the valve (3a); where the drive element (3) and thus the actuating element of the valve can be moved by means of a position controller (5) over a portion of the actuating distance to perform the partial-stroke freedom-of-movement test and thus to test the functionality of the actuator (1), and where the position controller (5) has a distance sensor (7)—the primary sensor—and a first evaluation unit (8) for evaluating and storing the signals of the distance sensor (7).

Abstract: In a method or system for function testing of a safety valve in engineering plant, it is tested whether the safety valve travels from a normal position to a predetermined final position in a certain operating situation of the plant. A bypass the valve bypasses the safety valve and assumes an idle position in a normal operation of the plant and a predetermined test position for function testing of the safety valve. The test position of the bypass valve is established such that a predetermined fluid flow through the bypass valve is permitted.

Abstract: The invention relates to a process control system having measuring devices and actuators. All of the measuring devices and actuators process information and exchange data amongst themselves. All measuring devices and actuators are interconnected to enable a bi-directional data exchange. Several, or all of the measuring devices and actuators can exchange data with a service unit that can be connected to the devices and actuators. The invention also relates to a method for operating a process control system of this type.

Abstract: In a method or device for function-monitoring an actuator in a process engineering plant, said actuator comprising a valve and an actuating drive for actuating said valve. A positioner is provided for setting a position of the valve, the positioner comprising a controller module. A predefined activation test signal is generated and applied to the controller module to position the actuator into a predefined function condition. A control signal is generated by the controller module for signalling the actuating drive in accordance with the activation test signal and an output control signal is sensed and monitored as compared to a reference control signal.

Abstract: Both improved protection against explosions and the possibility of performing diagnoses even when the I/P converter has been disconnected are to be provided by a position controller 5 for a pressure medium-operated actuating system, the controller being designed to be connected by a pneumatic line to a pneumatic drive 4-equipped actuator 1 of an actuating element, especially an actuating element of a safety valve 2, where the actuator 1 has an electric power line 6 for controlling an I/P converter 7 according to the live-zero principle, and where the I/P converter 7 can be driven by an electrically controlled switch 10. The goal is achieved in that the switch 10 is designed to be driven by an additional circuit 11, which is connected to the power line 6 and installed in the position controller and which monitors the current in the power line 6.

Abstract: The invention pertains to a method for verifying the performance of a test of the functionality of an actuator (1) with a drive (2) and a valve (3a), where the valve (3a) can be moved by the drive (2), which uses a drive element (3) acting on the valve (3a); where the drive element (3) and thus the actuating element of the valve can be moved by means of a position controller (5) over a portion of the actuating distance to perform the partial-stroke freedom-of-movement test and thus to test the functionality of the actuator (1), and where the position controller (5) has a distance sensor (7)—the primary sensor—and a first evaluation unit (8) for evaluating and storing the signals of the distance sensor (7).