Compare contact type and non-contact type speed measurement method.

1 Answer

Answer :

Contact type method
Non contact type method
Physical contact between meter and shaft 
No Physical contact between meterand shaft
Consists of moving parts
Does not consist of moving parts
Output is electrical signal 
Output has to be converted to electrical signal 
Optical transducer is not used
Optical transducer is used
ADC is required
ADC is not required
Maintenance is more due to the moving parts 
Maintenance is less 
Ex.AC / DC tachometer
Ex. Rotary Encoder, Photo electric tachometer

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