The Working Principle Of Optical Level Sensor

- Jul 09, 2019-

The working principle of the optical water level sensor, the product contains a infrared light-emitting diode and a photosensitive receiver. The light emitted by the LED is directed into the lens at the top of the sensor. When the liquid is immersed in the lens of the photoelectric level switch, the light is refracted into the liquid, so that the receiver does not receive or can only receive a small amount of light. The tank infrared level sensor in operating conditions, and the receiver can drive an internal electrical switch to activate an external alarm or control circuit. If there is no liquid, the light from the LED is reflected directly from the lens back to the receiver. 

Optical water level sensor theory

The optical level sensor will output a high voltage value or a low vlotage value according to water state or waterless state. When the prism of level sensor is in liquid, the level sensor will output a low voltage; When the prismm of level sensor is in air, the level sensor will output a high voltage. If you want to get a converse output logic, Shenzhen EPT Technology will offer the level sensor according to the requirement.


Shenzhen EPT Technology Co.,Ltd, a manufacturer of level sensor, flow sensor, tilt switch, tact switch, tip over switch and etc for over 16 years. If you have any questions, welcome to contact us.