Liquid level sensor apparatus and method of using thereof

Abstract

A liquid level sensor apparatus and a method of using thereof for determining the level of a conductive liquid held within a container, wherein the container is subject to the accumulation of residue as a consequence of the conductive liquid contained therein. The liquid level sensor includes a sensor part which has a voltage; a ground connection having an electrical polarity; a circumferential ring having a bias voltage opposite in polarity to the ground connection and a voltage corresponding to that of the sensor attached around the sensor; a float which is buoyant on the conductive liquid; and a conductive tip attached to the top of the float, the conductive tip being conductive with the sensor end when in at least one predetermined position. The bottom of the float is in contact and buoyant on the conductive liquid and the conductive liquid has a level wherein when the level rises, the float rises, and when the conductive tip reaches the at least one predetermined position, a circuit is completed to the ground connection which indicates a condition to the sensor tip. The bias ring prevents a false indication of the condition when residue is present on the container walls by preventing completion of the circuit from the sensor tip to the ground connection.