A method for testing a laboratory instrument and appropriate laboratory device.

摘要

The invention relates to devices for liquid level detection (LLD). It comes to a laboratory apparatus (100) having an electronic circuit (2) for detecting a liquid level in a liquid container (5), a deliverable sensor (3) which is connected to an input side (6) of the electronic circuit (2), and with a movement device that makes it possible to deliver in the liquid container (5) the sensor (3) in the direction of the liquid (1). Upon immersion of the probe (3) into the liquid (1) is caused in the electronic circuit (2) a change in capacitance, which gives a signal in the circuit (2). The laboratory unit (100) comprises a reference circuit (20) which is connected to the input side (6) of the circuit (20), and the effective capacitance on the input side (6) of the circuit (2) dictates. There comes a sequence control (30) are used, which causes the initiation of a test by applying a control signal (S1) to the reference circuit (20), wherein the control signal (S1) by a switching operation causes an increase in the effective capacity. The processing of the corresponding change in capacitance is monitored for example by the sequence controller (30).