Abstract:
In an electro-pneumatic system for controlling a double-acting pneumatic actuator having first and second working chambers, first and second preliminary pneumatic control components generate first and second preliminary pneumatic control signals transferred to respective first and second main pneumatic control components having outputs connected to the respective first and second working chambers. An electronic splitter circuit precedes the first and second preliminary pneumatic control components for splitting and inverting an electrical control signal input to the splitter circuit around an electrical mean control value to create first and second mirror-inverted electrical control signals respectively connected to the respective first and second preliminary pneumatic control components. The electrical mean control value is adjustable such that the first and second preliminary control components respectively generate the respective first and second preliminary pneumatic control signals mutually inverted around a pneumatic mean value.
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. The microprocessor, upon detecting a specific operational malfunctioning, actuating the positioning device and executing an emergency procedure according to which the same emergency signal is generated and output at the second signal transmission contact.
Abstract:
In an electro-pneumatic system for controlling a double-acting pneumatic actuator having first and second working chambers, first and second preliminary pneumatic control components generate first and second preliminary pneumatic control signals transferred to respective first and second main pneumatic control components having outputs connected to the respective first and second working chambers. An electronic splitter circuit precedes the first and second preliminary pneumatic control components for splitting and inverting an electrical control signal input to the splitter circuit around an electrical mean control value to create first and second mirror-inverted electrical control signals respectively connected to the respective first and second preliminary pneumatic control components. The electrical mean control value is adjustable such that the first and second preliminary control components respectively generate the respective first and second preliminary pneumatic control signals mutually inverted around a pneumatic mean value.
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. The microprocessor, upon detecting a specific operational malfunctioning, actuating the positioning device and executing an emergency procedure according to which the same emergency signal is generated and output at the second signal transmission contact.