The Ultrasonic sensor detects the distance of any object using its non-contact technology. It is set into repeatable mode, thus continuing to detect the distance of an object in range until the object is removed or the sensor is not turned on. The sensor is given a ten-second calibration time and after that, it runs. If the ultrasonic sensor detects an object farther than 20 cm until closer than 15 cm, then a corresponding LED light would turn on to signal the water level of the water storage.
This sensor contains lenses that determines its detection range. It is said to have a minimum and maximum range of 2 to 400 centimeters according to the manual. The sensor is then set to detect objects at varying distances.
According to the program, the sensor will send a high signal when it detects an object or obstruction within 15 cm to the maximum range from the sensor. The system was then tested with varying volumes of water at different times. This is to ensure the accuracy of the whole system.
LED Indicators are paired up with the ultrasonic set-up that turns on when the condition is met. Thus, if the ultrasonic sensor picks up the obstruction or object, an LED Indicator is given a high signal in accordance with the distance detected by the ultrasonic sensor. Less than or equal to 15 cm gives the red LED a high signal. More than 15 but less than or equal to 20 cm gives the yellow LED a high signal. More than 20 cm gives the green LED a high signal.