High Frequency Tank Sensors
Ultrasonic tank sensors (normally mounted in the top of a tank) use a very high frequency sound (ultrasound), at a pitch higher than humans can hear, to blast a momentary ping noise, which echoes off the surface of the fluid. The tank monitor detects the microscopic time delay between when it sends the ping and when it hears the ping’s reflected echo. The longer the time, the farther away the surface of the fluid and the lower the level of the fluid in the tank. The monitor calculates the level of the fluid in the tank from this echo delay.
