🔍 Key Concepts

• proportional controller behavior in a control loop • meaning of set point vs. measured/control point (process variable) • how steady-state error appears when only proportional control is used

💭 Think About

• In a P-only controller, what happens to the final measured value when there is a load change and the system settles? Does it always equal the set point? • Which two values are being compared when we talk about a persistent, stable difference that remains even after the system has settled? • Look at each choice and ask: which pair of terms could logically describe a steady-state difference in normal operation?

✅ Before You Answer

• Be clear on the definition of set point (the desired value) and control point/process variable (the actual controlled value). • Verify what dead band and proportional band mean and whether they are values that can directly differ as a steady-state error. • Confirm that offset in proportional control is another way of saying a constant steady-state error between the target and the actual condition.