Method for checking the operational capability of a final control device

A method for checking operational capability of a final control device, comprising:

• providing a final control device, comprising:
• a control valve displaceable via an actuating drive by an actuating element engaging with the control valve,
• a position sensor detecting the actual position of the actuating element, and
• an electropneumatic position controller generating a pneumatic controlled variable as a function of the actual position and a target position;
• a magnetic valve, the pneumatic controlled variable being supplied to the actuating drive via the magnetic valve;
• an instrumentation and control device,
• the magnetic valve being supplied with a supply voltage by the instrumentation and control device, and
• the magnetic valve, in the event of an emergency, being deactivated by switching off the supply voltage in order to vent the actuating drive;
• moving briefly the actuating element over a part of a displacement path in order to conduct a partial-stroke test;
• recording the displacement movement of the actuating element;
• deactivating briefly the magnetic valve such that the actuating element moves over only a part of the displacement path in order to conduct a magnetic valve test;
• supplying the supply voltage to the magnetic valve via a controllable switch;
• opening the controllable switch by a magnetic valve test signal generated by the instrumentation and control device in order to start the magnetic valve test;
• and
• supplying the magnetic valve test signal to the controllable switch via a limit switch controlled by the actuating element,
• wherein the limit switch is opened when the actuating element reaches a predefined position.