The usual conductivity range for a contacting sensor is 0 01 to 50 000 us cm.
Conductivity level sensor working principle.
Common cell constants are 0 01 cm 0 10 cm 1 0 cm and 10 cm.
Milk beer bases acids brine and apply 4 electrode sensors where a wide measuring range is required e g.
For frp or other plastic tanks an earth electrode is required.
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.
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.
The technique is frequently referred to as rf for the radio frequency signals applied to the capacitance circuit.
When the liquid covers the electrodes it forms a part of an electric circuit causing current to flow.
The tc sensor operating principle is based on temperature induced change of an electrically heated sensing element.
The sensor selection depends on the application and the conductivity range.
The sensor has a pair of electrodes and applies alternating current to them.
To measure low conductivities in pure and ultrapure water choose conductive sensors.
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.
Sensor uses conductivity between the electrode and the ground to detect a level.
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.
Readings are positive for hydrogen using air as the reference gas.
Capacitance level sensors excel in sensing the presence of a wide variety of solids aqueous and organic liquids and slurries.