| 摘要 |
The invention relates to devices for liquid level detection (LLD). It relates to a laboratory device having an electronic circuit for detecting a liquid level in a liquid container, a feeler, which can be advanced, and which is connected to an input side of the electronic circuit, and having a movement device, which allows the feeler to be advanced in the direction of the liquid in the liquid container. Upon the immersion of the feeler in the liquid, a capacitance change is caused in the electronic circuit, which triggers a signal in the circuit. The laboratory device comprises a reference circuit, which is connected to the input side of the circuit, and which specifies an effective capacitance on the input side of the circuit. A sequence controller is used, which causes the triggering of a test by the application of a control signal to the reference circuit, the control signal causing an increase of the effective capacitance through a switching procedure. The processing of the corresponding capacitance change is monitored by the sequence controller, for example. |
