Liquid Level Sensors

Liquid Level Sensors, device for measuring liquid level and converting it to an electrical signal to send to other instrumentation. Also called liquid level switches. They are designed to change state when immersed in a liquid. And are used to determine if a liquid or oil exists at a particular level in a container.

Types of Sensors

Liquid level sensors provide measurement of the height or position of a fluid surface. They are using a variety of different technologies and methods.

The different kinds of liquid level sensors include;

1. Optical sensors detect the decrease or change in transmission of infrared light emitted from a diode through a material.
2. Capacitive sensors apply radio frequency signals to a capacitance circuit to sense materials with dielectric constants ranging from 1.1 to 88 or more.
3. Conductive or resistance sensors use a low-voltage power source applied across separate electrodes. Level is interpreted based on the amount of resistance or conductance of the substance which carries the current.
4. Diaphragm or pneumatic liquid level switches rely on air pressure to push a diaphragm which engages a micro-switch inside the body of the unit.
5. Float sensors involve the opening or closing of a mechanical switch through either direct contact or magnetic operation from a device which floats on the surface of the measured liquid.