Abb Ag

Abb Technology Ag

Thomas Kleegrewe

Andreas Wahlmann

Detlef Pape

Andreas Stelter

Wolfgang Scholz

Urs E Meier

Peter Krippner

Heiko Kresse

Armin Gasch

Stefan Tabelander

Martin Dahl

Wolfgang Lasarzik

Stefan Engelke

Axel Bredemeyer

Manfred Klüppel

The disclosure relates to a method for increasing the availability of displacement/position measuring systems on the basis of potentiometers with a slider tap in a closed control loop, the controller of which is formed by a microcontroller which is supplied with the position of the slider via an analog/digital converter. At least part of the sensor range of the potentiometer is scanned on request by presetting a sequence of manipulated variables and an available control loop variable which represents the position value at a high sampling rate outside process tasks is recorded, to determine the exact position of a defective slider position of the potentiometer by evaluating the variable. The reference variable of the control loop is overloaded in a defined manner within the process task such that the defective slider position is passed over during the displacement/position measurement and an intact slider position is reached.

Method for increasing the availability of displacement/position measuring systems on the basis of potentiometers with a slider tap

An exemplary position regulator is disclosed which includes a regulation unit and a travel measurement system for activating an actuating drive for adjusting a control fitting to a predetermined position. A signal shaper is provided for outputting a travel signal to a superordinate device. To provide an undisturbed output of the travel signal, the signal shaper is connected in series in a transmission path between the travel measurement system and the regulation unit, and is connected in parallel with the regulation unit so as to transmit signals. The signal shaper can have a switch which is controlled by an alarm signal of the regulation unit, by which, in a first (e.g., inoperative) position, the travel measurement system is fed from the regulation unit, and, in a second (e.g., operative) position, the travel measurement system is fed from the signal shaper. The signal shaper can be automatically calibrated when the position regulator is activated, by comparing an output signal from the travel measurement system with a travel signal which is received by the regulation unit.

Position regulator

The disclosure relates to a digital position transmitter for control of an actuating element having a positioner in a process installation, with the position transmitter having a regulator with a dead band in order to suppress disturbance signals. It is proposed that the dead band in each case lags the set-value change asymmetrically with respect to the set value.

Digital position transmitter

The disclosure relates to a method for operation of a position regulator for control of a pneumatic drive for an actuating member in a process installation. The position regulator has a pneumatic system with at least one nozzle/bounce-plate system, in which the bounce plates are in the form of piezo bending bars. For damped ventilation and venting of the pneumatic drive in the event of failure of the electrical power, it is proposed that the level of the electrical power supply be monitored and that, if a predeterminable limit value is undershot, the piezo bending bars of the pneumatics are adjusted via the input signals of the pneumatics such that the pneumatically controlled valves, which are subject to a characteristic, of the amplifier are open precisely just so far that a damped movement of the pneumatic actuating drive takes place to a predeterminable limit position at the desired movement speed.

Method for operation of a position regulator

A method is disclosed for detecting the drive type of an actuator, e.g., a pneumatic actuator, having a positioner for operating a final control element in a process engineering plant. The actuator is connected to the positioner by a mounting set, the positioner comprising an electronic control unit, which uses a microcontroller to receive one or more input signals, and to output actuating signals to control the flow of gas to or from the chambers of a single-acting or double-acting pneumatic drive. The position feedback sensors are equipped with a rotational measuring system. During commissioning of the actuator, the relationship between the drive volumes and the position signal is found and compared with transfer characteristics of known drive types. Where there is a match between the transfer characteristic defined by the value pairs of the given actuator and one of the transfer characteristics of the known drive types, the identified drive type is assigned to the given actuator.

Method for detecting the drive type of an actuator (II)

The disclosure relates to an actuating drive having a position transmitter for control of an actuating element with a position in a process installation. The position transmitter is equipped with a rotary measurement system whose pivoting range is mechanically limited, with the rotary measurement system having a shaft which is connected to a pick-up lever in an interlocking and unconfusable manner, which pick-up lever is articulated by means of the actuating drive or the actuating element. The shaft and the rotary measurement system are connected to one another via a slipping clutch. Markings are arranged isoazimuthally with respect to the rotation axis of the shaft, on the shaft circumference, and include angle information about the angle of the marking position with respect to the pick-up lever. The digital position transmitter has a sensor system for identification and evaluation of the markings. The slipping clutch has hysteresis.

Actuating drive with a position transmitter

The disclosure relates to a method for testing the functionality of armatures, e.g., of safety armatures, in process control systems which are assigned a test device for implementing partial stroke testing and which are connected to a control device, which brings about actuation, in accordance with regulations, of the safety armature in an emergency. Prior to the start of the implementation of the partial stroke testing, a request signal is transmitted from the test device to the control device which is answered by the control device with an enable signal, the enable signal being issued as a function of the current process sequence at the armature.

Method for testing the functionality of armatures

The disclosure relates to a control device for a pneumatically operated actuator in the field of process automation, in particular for continuous control of material flows in the industrial environment. The control device has a communications interface for receiving an electrical setpoint value, and an output for the output of a pneumatic fluid, whose pressure is varied as a function of a control deviation. The received electrical setpoint value is suitable as a process parameter. The control device is connected via a communications channel to an actual-value encoder, which is designed to output an electrical signal corresponding to the actual value of the same process parameter.

Growing community of inventors

Minden, Germany

Thomas Kleegrewe