Sensor Fritz is screwed onto the top of the G1/8 anchor tube thread and operated via an M12x1 sensor cable at 24VDC (LED operation indicator GREEN). The Sensor detects the magnetic field. When the anchor of the solenoid valve moves, the magnetic field changes and the sensor detects when the valve has switched. The Sensor signals as soon as the anchor of the solenod valve is in contact with the opposite pole. The LED integrated in the plug confirms the successful switching (LED switching indicator YELLOW). To ensure switching accuracy and switching reliability, the rated current of the solenoid coil must be constant.