If there is any difference between the two response

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If there is any difference between the two response, the system drives the plant, via the actuating signal, to make a correction. If there is no difference, the system does not drive the plant. Examples air conditioning, lift, washing machine (water level control) System Configurations : ii) Closed- loop Control System (CLCS)
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19 BETR 2383 Control System Fundamental Controller Process Or Plant + - Error summing junction input Trans ducer Output transducer = sensor summing junction summing junction + + + + Disturbances 1 Disturbances 2 Closed-loop system Controller Output Actuator Process Sensor Desired output response System Configurations : ii) Closed- loop Control System (CLCS)
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20 BETR 2383 Control System Fundamental 20 OLCS CLCS CLCS OLCS OLCS & CLCS OLCS
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21 BETR 2383 Control System Fundamental System Configurations The differences between open and closed-loop system are:- Closed-loop System Open-loop System Have the feedback path Does not have the feedback path Output response: greater accuracy Output response: not accurate Less sensitive to noise, disturbances and changes in the environment Sensitive to noise, disturbances and changes in the environment The system can compare the output response with the input and make a correction of there is any difference The system cannot correct the disturbances. So it does not have any corrective action. More complex and expensive. Simple and inexpensive.
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22 BETR 2383 Control System Fundamental System Configuration Differences The differences between open and closed-loop system are:- Does not have a loop Thus, it does not have any corrective action Open-loop system Actual / current condition is taken as a data to calculate the necessary corrective action needed. Corrective action is needed to maintain the desired value. Positive / negative feedback Closed-loop system
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