The invention relates to a level indicator (100) for measuring the fill level of a container, with an electronic control and evaluation system (132, 232) and an interface (133, 233), that are positioned in a housing (131, 231); a sensor unit with a sensor and attachments; a signal cable (110, 210) for connecting the electronic control and evaluation system (132, 232) and the sensor unit; and a connecting device (120, 240), which produces both a mechanical connection between the sensor unit and the housing (131, 231) of the electronic control and evaluation system (132, 232), and an electrical connection between the interface (133, 233) of the electronic control and evaluation system (132, 232) and the signal cable (110, 210), such that both the mechanical and electrical connections produced by the connecting device (120, 240) are separable. The invention also relates to a process for assembling a level indicator (100) having a control and evaluation unit (130).