Programmable Logic Contollers

Description

Exam Manufacturing Process Control Concepts Mind Map on Programmable Logic Contollers, created by Eric Jean on 16/03/2016.
Eric Jean
Mind Map by Eric Jean, updated more than 1 year ago
Eric Jean
Created by Eric Jean over 8 years ago
75
1

Resource summary

Programmable Logic Contollers
  1. Specialized computers
    1. Control machines and processes
    2. Designed similar to that of other computers/PCs
      1. Unlike PC
        1. Deigned to operate in industrial environments
          1. special input/output interfaces
            1. control program languages
          2. Types
            1. Fixed
              1. Everything is in one module
                1. Power supply
                  1. CPU
                    1. I/O
                    2. Least common
                    3. Modular
                      1. Modifiable - Able to change it
                        1. Each function is its own module
                          1. Power supply
                            1. CPU
                              1. Each I/O is separate
                          2. I/O Configurations
                            1. Modular I/O
                            2. History
                              1. Designed in the 1970's
                                1. Automotive industry
                                  1. replaced mechanical relays
                                    1. Do NOT require excess wiring that relays need
                                    2. Now far exceed mech. relays
                                      1. Count
                                        1. Time
                                          1. Math functions
                                            1. Process analog and digital signals
                                          2. Advantages
                                            1. Increased reliability

                                              Annotations:

                                              • Once a program has been written and tested it can be downloaded to other PLCs
                                              1. Logic is contained in the PLC's memory
                                                1. No chance of making a logic wiring error
                                                2. Flexibility

                                                  Annotations:

                                                  • Original equipment manufacturers (OEMs) can provide system updates for a process by simply sending out a new program
                                                  1. Easier to change a program than rewire a circuit
                                                    1. Uers can modify the program in the field
                                                    2. Lower costs

                                                      Annotations:

                                                      • Originally PLCs were designed to replace relay control logic.  The cost savings using PLCs have been so significant that relay control is becoming obsolete, except for power applications.
                                                      1. If you require more than 6 control relays, it will be less expensive to install a PLC.
                                                      2. Communications Capability

                                                        Annotations:

                                                        • A PLC can communicate with other controllers or computer equipment
                                                        1. Networked to perform such functions as...
                                                          1. Supervisory control
                                                            1. Data gathering
                                                              1. Monitoring devices and processes
                                                                1. Downloading/Uploading of programs
                                                              2. Faster response time

                                                                Annotations:

                                                                • PLCs operate in real-time which means that an event taking place in the field will result in an operation or output taking place.
                                                                1. Objects spend only a short time in front of a sensor
                                                                  1. Require quick response capability
                                                                  2. Easier to Troubleshoot

                                                                    Annotations:

                                                                    • PLCs have resident diagnostic and override functions that allow users to easily trace and correct software and hardware problems.
                                                                    1. Can be watched in real-time as it runs
                                                                      1. Easier to find and fix problems
                                                                    2. Typical PLC Instructions
                                                                      1. XIC (Examine ON)
                                                                        1. XIO (Examine OFF)
                                                                          1. OTE (Output Energize)
                                                                            1. OTL (Output Latch)
                                                                            Show full summary Hide full summary

                                                                            Similar

                                                                            Definitions in AS chemistry
                                                                            Stephen Cole
                                                                            An Inspector Calls - Themes
                                                                            Emily Simms
                                                                            Organic Chemistry Functional Groups
                                                                            linpubotwheeds
                                                                            Digestive System Pre/Post Quiz
                                                                            mkelemete
                                                                            The Nervous System and Hormones (Part 1)
                                                                            Naomi Science
                                                                            a christmas carol
                                                                            maha.als10
                                                                            Characters in Merchant of venice
                                                                            inds12
                                                                            exothermic and endothermic reactions
                                                                            janey.efen
                                                                            Management 1. PT (3MA101) - 1. část
                                                                            Vendula Tranová
                                                                            NSI / PSCOD/ ASSD
                                                                            Yuvraj Sunar
                                                                            Diseño de Software
                                                                            Verny Fernandez