Method for optimising a wetting current and adapted device for monitoring sensors with contact switches

A method for optimizing a wetting current, intended to be implemented by a device for monitoring sensors with contact switches forming a circuit comprising a current source (A) supplied by a supply voltage, at least two assemblies including a contact switch (CT1, CT2) and a resistor (R1, R2) in series, said at least two assemblies (CT1/R1, CT2/R2) being wired in parallel, and an analog-to-digital converter (CAN) having a saturation voltage, the method comprising the following steps:

• a first step in which the current source (A) supplies the circuit with a nominal current by means of a first control bus;
• a second step in which, if a voltage (Vm) measured across the terminals of said contact switch/resistor assemblies (CT1/R1, CT2/R2) is greater than a predetermined threshold voltage (Vs), said threshold voltage (Vs) being selected so as to be lower than the supply voltage of the current source (A), then the current source is stopped and means for discharging the circuit are implemented by means of a second control bus;
• a third step in which, if the second step has brought about the stoppage of the current source (A) and the discharging of the circuit, then the current source (A) supplies the circuit again with a supply current equal to the nominal current reduced by a predetermined increment,
• wherein, at the end of the third step, the second step is implemented again until the voltage measured across the terminals of said two contact switch/resistor assemblies (CT1/R1, CT2/R2) is lower than the threshold voltage (Vs).