2. Sensors are mostly electronic devices used to monitor or capture something.

3. For example, an optical sensor to count the number of items on the treadmill.

4. A complete system that has a sensor and produces an electric output signal is called a transducer.

5. FEATURES

6. SUPPLY The sensors are designed for industrial DC voltages (usually in the automation they use 24 volts), ac or universal (both)

7. OUTPUTS If the electric output signal can be any value between certain limits, the sensor is analog. Typically, the controller receives the signal is digital and, therefore, uses an AD converter. If it can be only two values, for example, 120mv and 5v, the sensor will be digital.

8. APPLICATIONS Widely used in medicine, automation, robotics.

9. Medical Pulse Sensor

10. TYPES OF SENSORS Depending on your application there are various families and types of sensors for use

11. POSITION Compared with a reference, determine the physical location Potentiometer (resistance) Ultrasonic (measures time by acoustic waves) Encoders (angular motion) Inductive (capture ferromagnetic materials by varying the electromagnetic field) Capacitive (electrostatic field variation).

12. OPTICAL The transmitter sends the light that is captured by the receiver

13. TEMPERATURE The most common and cheapest is the thermocouple. But it is not accurate for temperatures below 1 ºC

14. MAGNETIC Detect magnets through the varying magnetic field