Hello friends, welcome ELECTRICAL ENCYCLOPEDIA. In this article, we will study about the open loop & closed loop system , their advantages and disadvantages.
OPEN LOOP CONTROL SYSTEM
A open loop control system is a system which does not have feedback, the control action is independent of the output. In this system, output is not compared with the input. Therefore this system is also known as Non-Feedback System.
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| BLOCK DIAGRAM OF OPEN LOOP CONTROL SYSTEM |
Examples of Open Loop Control System.
1. Immersion Rod - The rod heats the water but it does not know that how much water should be heated and for how much time, it just heats water.
2. Traffic Light - Time for each colour lamp (red,yellow and green) is fixed. The operation of lamp does not depends upon the traffic density. So, it is also open loop control system.
ADVANTAGES OF OPEN LOOP CONTROL SYSTEM
1. Open loop system are simple and economical.
2. Less maintenance is required and it is not difficult.
3. Proper Calibration is not problem.
DISADVANTAGES OF OPEN LOOP CONTROL SYSTEM
1. Open loop system are inaccurate.
2. They are not reliable.
3. They are slow.
CLOSED LOOP CONTROL SYSTEM
A closed loop control system is a system which have feedback, the control action depends upon output. In this system, output is compared with the input and error signal (if any) is produced. Therefore this system is also known as Feedback System.
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| BLOCK DIAGRAM OF CLOSED LOOP CONTROL SYSTEM |
EXAMPLES OF CLOSED LOOP CONTROL SYSTEM
Air-Conditioner- A.C are provided with thermostat and thermometer . Thermometer measures the actual room temperature and compares it with desired temperature. Then there is a thermostat which turns the compressor ON or OFF.
ADVANTAGES OF CLOSED LOOP CONTROL SYSTEM
1. These system are more reliable.
2. Closed loop system are faster.
3. A number of variables can be handled simultaneously.
DISADVANTAGES OF CLOSED LOOP CONTROL SYSTEM
1. Closed loop system are expensive.
2. Maintenance is difficult.
3. Installation is complex.
Thanks for reading.
Keep sharing and loving.
Thanks for reading.
Keep sharing and loving.