Analog and Digital Sensors

Digital sensor

  • It produces discrete digital output signal or voltage which is digital representation of quantity to be measured.

  • It produces binary output in the form of ones (1s) and zeros (0s).

  • They are used in various applications such as waste water, water and other industrial processes.

  • Digital sensor consists of sensor itself, cable and a transmitter.

  • Examples: Measurements such as pH level, conductivity, dissolved oxygen, ammonium, nitrate etc. are conducted using digital sensors.

 

Analog sensor

  • It produces continuous output signal or voltage which is proportional to quantity to be measured.

  • It produces analog output.

  • Quantities such as temperature, speed, displacement, pressure, strain etc. are analog quantities as they are continuous in nature.

  • Example: Temperature of liquid can be measured using thermometer or thermocouple which continuously responds to changes in temperature as liquid is heated up or cooled down.