Optical liquid level sensors are solid-state, meaning they have no moving parts to cause unreliability. They use infra-red light and can be used in environments where a traditional float switch would not be suitable.
The main positive side of an optical liquid level sensor is its compact size, solid-state design and reliability. However, while extremely accurate for point level sensing in high pressure, temperature and at times corrosive environments. They are less useful for continuous level measurement applications.
Optical liquid level sensors do not measure the liquid level, instead, they detect the presence or absence of liquid. Optical liquid level sensors consist of two main parts: An infra-red LED and a phototransistor that is accurately positioned at the base of the sensor tip.
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