What are the electrical methods of level measurement?

What are the advantages of conductive level measurement?

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  It is not expensive and its design is very simple
  
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  It is reliable
  
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  Less maintenance
  
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  The only moving part is the relay
  
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  The activation is done from a wide range of conductivities
  
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  It has no moving parts so it is really suitable for indicating the level for many water-based materials
  

What are the disadvantages of conductive level measurement?

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  The process substance must be conductive
  
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  We can only do the point detection measurement
  
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  There is a chance for sparkling so it is not suitable for flammable substances
  
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  There is a chance for malfunction if the conductive buildup occurs on the electrode holder
  

What are the applications of conductive level measurement?
In this type of level measurement, the ability of the process material to conduct the electric current is used to measure the level. So basically this method is mostly used for point measurement of liquid interfaces of relatively high conductivity. So we can check the level of water-based solutions such as brine solutions, acids, caustic solutions, and certain types of beverages.
Capacitive level measurement
The operation of this type of level measurement is based on the change of capacitance. The electric device has an ability to store energy and this is called capacitance, this type of measurement utilizes the advantage of dielectric constant. The working of a capacitive level transmitter is similar to that of a capacitor, the probe has a metal center rod which would act as a plate of the capacitor and the vessel wall would act as the second plate. If the process material that is to be measured is non-conductive then it acts as the dielectric insulator between the two plates. If the process material is conductive then the probe insulation is the dielectric material in the capacitor. If the process material comes in contact with the probe then there would be a value reading if more products come in contact with the probe then the value reading will be high. This value reading or pF reading is the measure of capacitance and it is proportional to the product, or it shows the product height.