摘要 |
<p>A sensing device includes at least one electrode pair (2, 3, 4) and one sensing circuit (140) connected to the electrode pair (2, 3, 4). The sensing circuit (140) switches the value of its own output voltage when a substance establishes contact across the electrodes (2, 3, 4). The device further includes one output circuit (180) connected to the output of the sensing circuit (140) and adapted to provide an output signal (s7) representative of the presence of a substance across the electrode pair (2, 3, 4). The device also allows the output signal to take different voltage and/or current and/or frequency values, in particular such that values can be discerned which are representative of the presence or level of substances and/or representative of faults of the device.</p> |