v1 which is standing at terminal 18 comparator u1 switches its output at terminal 14 to a logic zero which it does by effectively connecting terminal 14 internally to ground capacitor c1 discharges to ground through the output of u1 and remains discharged so long as the voltage at terminal 12 remains below the first threshold reference voltage v1 the voltage at terminal 20 of u2 is lower than the threshold voltage v2 at terminal 24 and comparator u2 holds its output voltage terminal 22 at a logic zero level transistor q1 is therefore non conductive preventing current through the bridge 30 the timer motor 36 has no power whenever the sensor becomes non conductive u1 produces a logic 1 at its output 14 and the capacitor starts to charge gradually due to current flow through the resistor r8 this creates a time delay between the cessation of current in the sensor s1 and the actuation of u2 whenever the sensor is again touched by wet clothes the capacitor is again very rapidly discharged when the sensor again becomes dry the capacitor must start charging again from zero voltage so as to start its time delay anew without turning on the timer motor thus the motor.