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A device for sensing a level of a fluid, the device including a microcontroller and a probe coupled to the microcontroller. The microcontroller applies a given DC potential to the probe for a first period of time, measures a voltage associated with the level of the fluid to be sensed after the first

A device for sensing a level of a fluid, the device including a microcontroller and a probe coupled to the microcontroller. The microcontroller applies a given DC potential to the probe for a first period of time, measures a voltage associated with the level of the fluid to be sensed after the first period of time, and applies a reference DC potential to the probe for a second period of time.

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1. A device for sensing a level of a fluid by means of a probe having an impedance across first and second outputs, wherein the impedance varies depending upon whether the probe is at least partially immersed in the fluid to be sensed or not so immersed; the device comprising:a capacitor connected i

1. A device for sensing a level of a fluid by means of a probe having an impedance across first and second outputs, wherein the impedance varies depending upon whether the probe is at least partially immersed in the fluid to be sensed or not so immersed; the device comprising:a capacitor connected in series with one output of the probe; means for applying a DC potential to the capacitor for a first period of time so that the voltage across the capacitor is a function of the probe impedance; means for measuring a voltage associated with the voltage across the capacitor after said first period of time, said measured voltage indicative of whether the probe is immersed or not immersed in said fluid; and means for at least partially discharging the capacitor after the means for measuring a voltage associated with the voltage across the capacitor has measured said voltage, wherein said means for at least partially discharging the capacitor does so by applying a second DC potential to the capacitor for a second period of time so as to minimize probe damage. 2. A device for sensing a level of a fluid by means of a probe having an impedance across first and second outputs, wherein the impedance varies depending upon whether the probe is at least partially immersed in the fluid to be sensed or not so immersed; the device comprising:a capacitor connected in series with one output of the probe; means for applying a DC potential to the capacitor for a first period of time so that the voltage across the capacitor is a function of the probe impedance; means for measuring a voltage associated with the voltage across the capacitor after said first period of time, said measured voltage indicative of whether the probe is immersed or not immersed in said fluid; and means for at least partially discharging the capacitor by applying a second DC potential to the capacitor for a second period of time so as to minimize probe damage; wherein the means for applying a DC potential to the capacitor, the means for measuring a voltage associated with the voltage across the capacitor, and the means for discharging the capacitor are a microcontroller under programmed instruction. 3. A device according to claim 2, further comprising a resistor in series between the capacitor and the microcontroller.4. A device according to claim 3, wherein the microcontroller means for measuring a voltage associated with the voltage across the capacitor is connected to the series junction of the capacitor to the resistor.5. A device for sensing a level of a fluid by use of a probe having an impedance that changes depending upon whether the probe is in contact with the fluid or not in contact with the fluid, comprising:a driving circuit having at least a capacitor connected in series with the probe; and a microcontroller having an output in communication with said capacitor, and having an input for sensing voltage that is in communication with said driving circuit, wherein the microcontroller is programmed to apply a DC signal voltage to the driving circuit via said output for a first period of time, to measure the voltage at said input after said first period of time, and to apply a DC reference voltage to the driving circuit via said output after said voltage is measured, said reference voltage applied to the driving circuit for a second period of time so as to substantially discharge the driving circuit. 6. A device for sensing a level of a fluid as defined in claim 5, wherein the driving circuit comprises a series connection of a resistor with the capacitor, and wherein the microcontroller input is connected to the junction of the resistor and the capacitor.7. A device for sensing a level of a fluid as defined in claim 6, wherein the input of the microcontroller is connected to a second resistor at one end, with the other end of said second resistor connected to the series connection of the resistor and capacitor forming the driving circuit.8. A device for sensing a level of a fluid as defined in claim 7, wherein the signal voltage has a value of approximately five volts and wherein the reference voltage has a value of approximately zero volts.9. A device for sensing a level of a fluid as defined in claim 8, wherein the microcontroller input is an analog type input for measuring an analog voltage.10. A device for sensing a level of a fluid as defined in claim 7, wherein the probe has a primarily resistive impedance of approximately 7,000 ohms when in contact with water and wherein the resistor of the driving circuit is approximately 1,000 ohms, the capacitor of the driving circuit has a capacitance of approximately 0.22 microfarad and the second resistor has a resistance of approximately 10,000 ohms.11. A device for sensing a level of a fluid as defined in claim 5, wherein the signal voltage has a value of approximately five volts and wherein the reference voltage has a value of approximately zero volts.12. A device for sensing a level of a fluid as defined in claim 5, wherein the microcontroller input is an analog type input for measuring an analog voltage.13. A device for sensing a level of a fluid as defined in claim 5, further comprising an output circuit in cooperative engagement with the microcontroller for controlling at least one external device based on the voltage measured at the microcontroller input.14. A device for sensing a level of a fluid as defined in claim 13, wherein the voltage measured at the microcontroller input has a first range indicative of the probe in contact with the fluid and a second range indicative of the probe not in contact with the fluid.15. A method for sensing a level of a fluid by use of a probe having an impedance that changes depending upon whether the probe is in contact with the fluid or not in contact with the fluid, and further by use a driving circuit having at least a capacitor connected in series with the probe, comprising the steps of:applying a DC signal voltage to the driving circuit for a first period of time; measuring the voltage of the driving circuit after said first period of time; and applying a DC reference voltage to the driving circuit after said voltage is measured, said reference voltage applied to the driving circuit for a second period of time so as to substantially discharge the driving circuit. 16. A method for sensing a level of a fluid as defined in claim 15, wherein the driving circuit comprises a series connection of a resistor with the capacitor, and wherein the measuring of the voltage of the driving circuit is made at the junction of the resistor and capacitor.17. A method for sensing a level of a fluid as defined in claim 16, wherein the signal voltage has a value of approximately five volts and wherein the reference voltage has a value of approximately zero volts.18. A method for sensing a level of a fluid as defined in claim 15, wherein the signal voltage has a value of approximately five volts and wherein the reference voltage has a value of approximately zero volts.19. A method for sensing a level of a fluid as defined in claim 15, further comprising controlling at least one external device based on the voltage measured.20. A method for sensing a level of a fluid as defined in claim 19, wherein the voltage measured has a first range indicative of the probe in contact with the fluid and a second range indicative of the probe not in contact with the fluid.21. A method for sensing the level of a fluid as defined in claim 15, wherein the step of applying a signal voltage to the driving circuit, the step of measuring the voltage of the driving circuit, and the step of applying a reference voltage to the driving circuit are each performed by a microcontroller under programmed instruction.