Measuring device for monitoring level of liquid in machine or system

A measuring device for monitoring the level of liquid in a machine or system has a housing which has a thread for screwing the housing into a compressor and which is provided with a chamber which, in the screwed-in state of the housing, is fluidically connected to a fluid region of the machine or system to be detected; and a floating body arranged in the chamber, which floating body rotates about an axis of rotation as a function of the liquid level in the chamber, and which has a magnetic signal transmitter, which interacts with a magnetic field sensor arranged outside the chamber in order to detect the position and/or rotation of the magnetic signal transmitter, the floating body is arranged in the chamber in such a way that, in the absence of a fluid in the chamber, the floating body is oriented by gravity in a predefined base position independently of a screw-in rotational position of the housing generated when the housing is screwed into the machine or system, and wherein the floating body is oriented by