PRE-TEST TOPIC 1 PLC TECHNOLOGY

What is Programmable Logic Controller (PLC) ?

• An internal communications highway also known as a bus system, carries information to and from the CPU, memory and I/O units under the control of the CPU.

• Provides the voltage needed to run the primary PLC components

  
  

• Is a digital operating electronic apparatus which uses a programmable memory for internal storage of instruction for implementing specific function such as logic, sequencing, timing, counting and arithmetic to control through analog or digital input/output modules various types of machines or process.

  
  

• Provides signal conversion and  isolation between the internal logic-   level signals inside the PLC and the field’s high level signal.

  
  

Advantages of PLC except

• Expensive

• Reliable components make these likely to operate for years before failure.

• Easier and faster to make changes.

• • Less wiring.

Major components of PLC except

• Power Supply

• Input Module

• Processor

• Outlet

Example of input module except

• Solenoid

• Push Button

• Limit Switch

• Sensor

Choose the main function of power supply

• Provides signal conversion and  isolation between the internal logic-   level signals inside the PLC and the field’s high level signal.

• Provides the voltage needed to run the primary PLC components

• Provides intelligence to command and govern the activities of the entire PLC systems.

  
  

• used to enter the desired program that will determine the sequence of operation and control of process equipment  or driven machine.

  
  

Choose the main function of processor

• used to enter the desired program that will determine the sequence of operation and control of process equipment  or driven machine.

  
  

• Provides the voltage needed to run the primary PLC components

• Provides intelligence to command and govern the activities of the entire PLC systems.

• Provides signal conversion and  isolation between the internal logic-   level signals inside the PLC and the field’s high level signal.

Example of output module except

• alarms

• push button

• solenoid

• lamp

Choose the suitable action in Phase 1

• Read Inputs Scan

• Write Inputs Scan

• Write Output Scan

• Read Output Scan

Choose the right input module

• sensor

• alarm

• push button

• limit switch

Choose the output module

• push button

• limit switch

• lamp

• solenoid