Capacitive Sensor For Water Level Measurement

They are also widely used in water treatment applications for pump control and open channel flow measurement.

Capacitive sensor for water level measurement. Capacitive water level sensor is manufactured on well developed capacitive technology and widely used for liquid level measurement. The sensors emit high frequency 20 khz to 200 khz acoustic waves that are reflected back to and detected by the emitting transducer. Capacitive level transducer is an example of indirect measurement of level capacitance level sensors are used for wide variety of solids aqueous and organic liquids and slurries. 5 v pp 3 khz ac signal is used as input signal for the system.

Capacitive measurement has a very fast response time which makes it ideal for processes with fast level changes and small containers. Performing system calibration using labview software can help achieve higher accuracy. In this research water level sensor based on capacitive principal created using two copper plates with height h width b and distance l between two plates respectively 0 040 m 0 015 m and 0 010 m. The capacitive level measurement can be used in aggressive media when a fully coated probe e g.

1 have described the design and implementation of a liquid level measurement system based on a remote grounded capacitive sensor. Also capacitive sensor is a noncontacting device in the common usage. The technique is frequently referred as rf as radio frequency signals applied to the capacitance circuit. Applications tank level monitoring in chemical food water treatment power and brewery industries.

A rod of stainless steel and a polytetrafluoroethylene ptfe insulated wire have been used for electrode of capacitive sensor. The measurement principle is not affected by the density variation of the media. Dielectric constant between two plates is proportional to water level. Capacitance level sensors operate in the way that process fluids have dielectric constants significantly different to air.

For d h 1. ε r eff 1 ε r 2 from this equation the measured capacitive is proportional to the length submerged into water as the approximate capacitance per length of track for a coplanar sensor remains constant. Ultrasonic level sensors are used for non contact level sensing of highly viscous liquids as well as bulk solids. It has typically high impedance sensor particularly at low frequencies as clear from the impedance reactance expression for a.

Capacitive liquid level sensors have been widely used for water fuel oil etc. An effective interdigital capacitive sensor for the water level measurement range of 0 30 cm with 0 2 cm resolution has been proposed designed and realized. They measure the change in capacitance between two plates produced by changes in level.