Method and device for monitoring the orientation of a measuring device and measuring device

The method involves using a monitoring device with a bubble inclination sensor whose bubble (12) position is measured optically by a radiating element (D1) on one side and a receiving sensor element (D2) on the opposite side of the bubble forming a sensing axis. Reference elements (D3,D3') on either side of the sensor element receive the radiation to check whether the radiation intensity is in a permitted range.. Independent claims are also included for the following: (A) a monitoring device for implementing the inventive method (B) and a measurement device, especially a balance, with an inventive monitoring device.