The document discusses different types of sensors and components used in automation systems. It describes the principles of solenoid valves, relays, magnetic encoders, and optical encoders. It defines sensitivity and resolution for sensors and explains that relays contain an electromagnet, spring, armature, and contacts. It also lists the types of solenoid valves as 2-way, 3-way, 4-way, and pilot operated.

2. content
 Sensitivity vs. Resolution
 Types of solenoid valve
 Principle of work of relay
 Types of relay
 Principle of work of magnetic encoder
 Principle of work of optical encoder

3. Sensitivity vs. Resolution
 Sensitivity
It’s a measure of the variation caused in the output by
changes to the inputs of the system.
 Resolution
It’s the smallest increment of data that can be detected

4. Relay
 It’s a switch operated electrically and mechanically
 It consists of
1. Electromagnet
2. Spring
3. Movable armature
4. Switch point contacts

5. Principle of work

6. Principle of work

7. Types of relay

8. Types of solenoid valve
 2 way solenoid valve .
 3 way solenoid valve .
 4 way solenoid valve .
 Pilot operated solenoid valve .

9. Types of solenoid valve
 2 way solenoid valve

10. Types of solenoid valve
 3 way solenoid valve

11. Types of solenoid valve
 4 way solenoid valve

12. Types of solenoid valve
 Pilot operated solenoid valve

13. Magnetic encoder
 It consists of
1. a scale ( ferrous metal )
2. a pick up ,consists of a permanent magnet and
sensing element

14. Principle of work
 When the scale moves ,the ferrous metal disturb the
magnetic flux emitted by permanent magnet.
 This makes the flux expand or collapse
 these changes are sensed by the sensing element
 Then sensing element generates digital or pulsed signal
output

15. Rotary magnetic encoder

16. Optical encoder

17. Optical encoder