In Chapter 1, you have learned about sequence control.

In this chapter, let's learn about programmable controllers.

• 2.1 History
• 2.2 Relays
• 2.3 Differences Between Relay Control and Sequence Control
• 2.4 Features of Programmable Controllers and Personal Computers
• 2.5 Structure of Programmable Controllers
• 2.6 Basic Knowledge of Contacts
• 2.7 Operation of Programmable Controllers
• 2.8 Programs