What are the electrical methods of level measurement?

What are the advantages of capacitive level measurement?

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  It can operate at extreme pressure and temperature conditions
  
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  It is very reliable and economical
  
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  It has less moving parts and less maintenance is needed
  
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  Installation is very easy, and it can be used for different types of vessel
  
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  It has a good measurement range
  

What are the disadvantages of capacitive level measurement?

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  It is intrusive
  
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  It won’t work well with a varying dielectric material
  
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  Certain process materials such as acids and caustics which won’t appear to coat the sensing element are highly conductive so error measurements could happen because of the thin film they leave
  

What are the applications of capacitive level measurement?

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  It is used in pharmaceutical industries to control the slurry level
  
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  It is used in the food and packing industries
  
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  It is used in chemical industries to check the level of the substances
  
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  It can be seen in paints and pigment industries to check the level of the fluids
  
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  It can be used with corrosive materials like hydrofluoric acid
  
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  It can be used with liquid metals at a very high temperature
  
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  It can be used with very high-pressure industrial processes
  

Resistance type level measurement
This type of level measurement utilizes the electrical relationship between the resistance and the current flow in order to measure the level. This sensor measures the level by changing its resistance when the level changes. Then the measured resistance would be converted into an electrical signal which would be proportional to the level of the liquid in the tank. The below image is of the resistance tape level sensor and this consists of a metal base strip and a wire winding. When the sensor is placed in a liquid, the pressure will cause the winding to contact the base strip, this contact would create a change in resistance of the wire. It has an internal transmitter that can convert the resistance measurement to a 4-20ma output.

What are the advantages of resistive type level measurement?

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  When compared to other electrical level sensors the resistance type level detectors only need less maintenance.
  

What are the applications of resistance type level detectors?

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  It can be used for liquid gas interfaces and also for slurries and solids
  
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  This type of level measurement can be used to measure raw sewage, sludge, and gasoline levels