The difference between the indication of the instrument and the actual value of the measured variable is known as what?

The difference between the indication of the instrument and the actual value of the measured variable is referred to as an error in the measuring instrument. This concept is crucial in control systems, as accurate measurements are essential for effective monitoring and control. When an instrument shows a value that deviates from the true value of the variable being measured, this discrepancy is termed an error.

In practice, understanding this error is important for calibrating instruments and ensuring that control systems operate within the desired parameters. The measurement error can arise from various factors, including instrument drift, environmental conditions, or inherent limitations in the measuring technology. Recognizing and correcting these errors allows for improved accuracy and reliability in control applications.

Other terms listed, such as the controlled variable and set point, relate to different aspects of control systems. The controlled variable is the parameter being regulated, while the set point is the desired value that the controlled variable should attain. Discarded suggests something that is no longer useful or relevant, which does not accurately describe the relationship between the instrument indication and actual value.