Here are the simple techniques that will help you to work and some abbreviation’s in CONCEPT OF PLC(Programmable Logic Control).

Some Abbreviation Used in CONCEPT OF PLC(Programmable Logic Control)

1. LL: LADDER LOGIC
2. HMI: HUMAN MACHINE INTERFACE
3. BCD: BINARY CODED DECIMAL
4. MMI: MAN MACHINE INTERFACE
5. MODICON: MODULAR DIGITAL CONTROLLER
6. RIO: REMOTE I/O
7. MSB: MOST SIGNIFICANT BIT
8. RF: RADIO FREQUENCY
9. RTU: REMOTE TERMINAL UNIT
10. TCP: TRANSMISSION CONTROL PROTOCOL
11. IP: INTERNETPROTOCOL
12. LSB: LEAST SIGNIFICANT BIT
13. IEC: INTERNATIONAL ELECTRO-TECHINAL COMMISSION
14. PID: PROPORTION INTEGRATED DERIVATIVE
15. SCADA: SUPERVISOR CONTROL AND DATA ACQUISITION
16. EIA: ELECTRONIC INDUSTRIES ASSOCIATION
17. I/O: INPUTs AND OUTPUTs
18. DIO: DISTRIBUTED I/O

MEANING OF CONCEPT OF PLC(Programmable Logic Control)

Programmable Logic Control are a specialized computer used for automation of electromechanical processes such as arithmetic, sequencing, timing, counting, operation data manipulation, control of machinery on factory assembly lines, communication, lighting fixtures, immunity to electrical noise, control industrial processes based on the input instructions given to the controller and resistance to vibration and they usually store information in non-volatile memory and also it works like real time system thereby giving you the output of what you inputted.

PARTS THAT MAKE UP A PLC

1. Power supply module
2. Base unit
3. Memory board
4. CPU module
5. I/O controller/connecting cable
6. Analog input module
7. Analog output module
8. Cable for connecting peripheral devices
9. Communication module
10. Counter module
11. Input module
12. Output module
13. Dummy module.
14. These are the different parts or module that are fix together in other to construct PLC which helps to carry out many functions as specified in the definition above.

REQUIREMENTS (SPECIFICATIONS) TO BE CONSIDERED WHEN WORKING ON PLC

1. The input and output interface (the interface of the input and output of the PLC had to be easily replaced.
2. The ability to survive any industrial environmental condition.
3. The controller had to be in module form (the controller unit had to be design in way in which it be repair or replace any damage sub-assemblies parts.
4. To consider weather the system is reusable.
5. You had to ensure that the method used to program the controller is simple in other to be operated by another user that has a little knowledge of PLC.
6. To ensure that the control system has the ability and capability to communicate with the data collection to the brain of the system or central system.

APPLICATION OF PLC

As the name implies, programmable logic control, which means it can be used in many varieties of industries for process control and also, it can be used in the following areas in the industries.
Here are the area where it’s applicable :

1. Air compressors (for stationary and mobile and it uses 12 VDC OR 120 VAC).
2. Car washes ( for process control and it uses 24 VAC OR 24 VDC OR 120 VAC).
3. portable water purification ( for disinfect water for drinking and it uses 12 VDC).
4. Residential irrigation control ( for time controlled fertilizing and it uses 24 VDC).
5. Recreational vehicle monitoring system ( for monitors generator and AC voltage and it uses 12 VDC).
6. Press control and safety ( for stamping and clutch monitoring and it uses 120 VDC).
7. Airport runway lighting control ( for remote or from tower and it uses 120 VDC).
8. Liquid vitamin dispenser for livestock (regulation of vitamin dispensed in food and it uses 24 VDC and 120VAC).
9. Remote power sources ( for recharging portable device when traveling and it uses 12VDC and 120VAC).
10. Packaging equipment ( for various types such as : vegetable, stretch wrap, shrink wrap etc) and it uses 120VAC).
11. Oxygen refilling equipment
12. Condensation control
13. Vacuum pump system
14. Wet well pump control
15. Movie theater control
16. Injection molding
17. Smoke house control
18. Process control
19. Aggregate testing system
20. Recycling equipment.

WORKING PRINCIPLE OF PLC (OPERATIONS)

The operation of PLC work with the principal of cycling sequentially. And they are as follows :

1. Input scan
2. Program scan
3. Output scan
4. Maintenance.

The four steps above work hand in hand to achieve a specified purpose.
The input scan helps to detects the state of all input devices that are connected to the PLC.
After which the program scan will took over and executes the user created program logic.
Then, the output scan will de-energize or energized all output devices that are connected to the PLC and Finally, maintenance will help to communicate with the programming terminals and internal diagnostics.(note: all the steps are processed in a continually loop).

Conclusion

The invention of PLC is to solve the problem of relay controlled system.