Thank you for your interest in Sump Pumps Direct. The LevelGuard switch works based on Field Effect sensing technology that was developed by TouchSensors, Inc out of Wheaton, IL.
Field-Effect sensors are digital, solid-state electronic devices that can detect conductive materials such as water or the human touch. The sensor�s cell design uses an integrated circuit (IC) that switches its output state when the conductive target is sensed. A Field-Effect cell is comprised of three main elements, the IC, a unique sensing electrode geometry, and two tuning resistors. Moreover, Field-Effect requires no moving parts, floats, software, or any other mechanism to operate.
When 5 VDC is supplied to the sensor, a low power, invisible field is created. The field emanates directly through any protective dielectric barrier such as plastic or glass that may surround or cover the sensor. When a conductive object or material enters the field, the sensor detects the change and indicates an event has occurred with a corresponding output signal. The input stimulus to the field is typically water in most liquid level sensing applications, as is the case in TouchSensor�s� LevelGuard Home Sump Pump Control product line.