Lesson Notes By Weeks and Term v4 - SHS 3
AUTOMATION TECHNOLOGIES
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AUTOMATION TECHNOLOGIES
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Subject: Engineering
Class: SHS 3
Term: 2nd Term
Week: 19
Grade code: 3.4.1.LI.2
Strand code: 4
Sub-strand code: 1
Content standard code: 3.4.1.CS.1
Indicator code: 3.4.1.LI.2
Theme: AUTOMATION AND EMBEDDED SYSTEMS
Subtheme: AUTOMATION TECHNOLOGIES
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Welcome, future engineers! Look around you in Ghana today. At the Tema Port, giant cranes move containers with precision. In factories producing FanMilk or Kasapreko, bottles are filled, capped, and packed at incredible speeds. Even the traffic lights that control the flow of cars in Accra and Kumasi work automatically. This is all possible because of Automation. Automation uses control systems, like computers and robots, to control industrial machinery and processes, replacing manual human effort. The "brain" behind most of modern industrial automation is a special, rugged computer called a Programmable Logic Controller (PLC).
2.1 What is a Programmable Logic Controller (PLC)?
A PLC is a robust industrial computer designed to withstand harsh environments (dust, moisture, heat, vibration) and perform control functions. Think of it as the brain of an automated machine. It takes in information from its "senses" (input devices), processes this information according to a program you write, and then sends out commands to its "muscles" (output devices).
Core Parts of a PLC: Central Processing Unit (CPU): The actual brain. It runs the program and makes decisions. Input Modules: These are the connection points for input devices like switches and sensors. They convert the electrical signals from these devices into a format the CPU can understand. Output Modules: These are the connection points for output devices like motors, lights, and valves. They take the CPU's commands and convert them into electrical signals powerful enough to operate these devices. Power Supply: Provides the correct voltage to power the CPU and modules. Programming Device: A laptop or special handheld device used to write, edit, and download the program to the PLC's memory. 2.2 Components of an Automation System
An automation system is made of three main types of components, all connected to the PLC.