Conductivity Level Sensor Working Principle

Common cell constants are 0 01 cm 0 10 cm 1 0 cm and 10 cm.

Conductivity level sensor working principle.

Use toroidal sensors in media with high conductivity e g. Ultrasonic level instruments works on the basic time of flight principle which states that sending a sound wave from a peizo electric transducer to the contents of the vessel which may contain liquid solid or slurries level. Readings are positive for hydrogen using air as the reference gas. To measure low conductivities in pure and ultrapure water choose conductive sensors.

The tc sensor operating principle is based on temperature induced change of an electrically heated sensing element. The sensor has a pair of electrodes and applies alternating current to them. Milk beer bases acids brine and apply 4 electrode sensors where a wide measuring range is required e g. When the liquid covers the electrodes it forms a part of an electric circuit causing current to flow.

Because a given cell constant can be used only over a limited range two possibly three cell constants are required to cover the entire range. Once the liquid reaches the fill limit determined from the installation height of the electrode the liquid medium closes the dc free alternating current circuit between the two electrodes or between the container wall and an electrode. Measurement principle the conductivity of a liquid medium may vary widely. Higher conductivity samples require larger cell constants.

Conductivity could in principle be determined using the distance between the electrodes and their surface area using ohm s law but generally for accuracy a calibration is employed using electrolytes of well known conductivity. The usual conductivity range for a contacting sensor is 0 01 to 50 000 us cm. Capacitance level sensors excel in sensing the presence of a wide variety of solids aqueous and organic liquids and slurries. The technique is frequently referred to as rf for the radio frequency signals applied to the capacitance circuit.

For frp or other plastic tanks an earth electrode is required.