1. Electro-Optic
The electro-optic type level sensors utilise their infrared LED light and receiver to detect. The LED is positioned and directed into a prism which forms the tip of the sensor. As soon as the media (liquid) touches the prism, it disrupts the light and senses the change. This change can relay to an electronic switch (ie. actuating an alarm or circuit).
2. Ultrasonic
The ultrasonic type level sensors have no moving parts and require absolutely no maintenance. It offers an alternative to the generic reed switches and are ideal for applications where foam and condensation could affect the sensor. The ultrasonic pulses emitted reflect off liquid surfaces and the gap area therefore detects its presence or absence.
3. Capactive
The capactive sensors are specifically calibrated to each medium, in order to account for a number of variables. They can be used on aqueous and non-aqueous fluids regardless of transparency or colour. Once the factory preset or customer-set trigger point is actuated, the sensor can then switch to the required output.
4. Float
The float sensors operate on perhaps the most common and simple principle on the market. As the float rises or lowers, the magnetic field actuates the encapsulated reed switch to its required setpoint. Depending on design these can be mounted vertically or horizontally.
5. Radar
This is also referred to as guided wave radar or guided microwave. Very similiar to the ultrasonic principle of operation, except these pulses can travel up to the speed of light. This provides a very high accuracy and repeatability for the users.