Abstract: A measuring instrument, in particular a flow or level meter, includes a base module for the acquisition and processing of measured data and an add-on module. Both the base module and the add-on module feature an optical interface interconnecting the base module and the add-on module. The result is a measuring instrument which, by interchanging the add-on module, can be equipped with various external interfaces without requiring any recalibration of the measuring instrument.

Abstract: A measuring instrument, in particular a flow or level meter, includes a base module for the acquisition and processing of measured data and an add-on module. Both the base module and the add-on module feature an optical interface interconnecting the base module and the add-on module. The result is a measuring instrument which, by interchanging the add-on module, can be equipped with various external interfaces without requiring any recalibration of the measuring instrument.

Abstract: A suspended-body flow meter for flowing media of the type having a measuring tube, a suspended body that can move in the flow direction and is arranged in the measuring tube, at least one permanent magnet connected to the suspended body, at least one rotatably mounted follower magnet that follows the movements of the permanent magnet connected to the suspended body and arranged outside the measuring tube and a display device converting the movements of the follower magnet, the follower magnet being constructed as an annular permanent magnet. In the suspended-body flow meter, scales with the same spread can be used regardless of the nominal width of the measuring tube and without requiring special aids or corrective means due to the fact that the annular follower magnet is magnetized laterally and on its coupling part closer to the measuring tube, the north pole and the south pole form an angle of preferably about 90.degree..