Apparatus for ascertaining and/or monitoring at least one fill level of at least one medium in a container according to a travel-time measuring method and/or a capacitive measuring method

An apparatus for ascertaining and/or monitoring at least one fill-level of at least one medium in a container according to a travel-time measuring method and/or a capacitive measuring method, which comprises:

• at least one measuring probe;
• a capacitive measurement circuit, which produces a low-frequency measurement signal on the measuring probe and through this performs an ascertainment of the capacitance or a reactance;
• a time-domain reflectometer measuring circuit, which produces a high-frequency, electromagnetic signal sent out as a sent signal, which receives a reflection signal as an echo, and through a time difference between the sending of the sent signal and the receipt of the reflection signal a travel-time or a travel-time dependant echo curve is ascertained;
• a control/evaluation unit, which controls both of said measurement circuits and which from the ascertained capacitance, the ascertained travel-time and/or the ascertained travel-time-dependant echo curve ascertains fill-level;
• and
• a diplexer, which sends the low-frequency measurement signal and the high-frequency, electromagnetic measurement signal to the measuring probe and effects a signal separation of the high-frequency, electromagnetic measurement signal into the first signal path of said time-domain reflectometer measurement circuit and the low-frequency measurement signal into said second signal path of said capacitive measurement circuit.