Answer / himanshu apte

As i understand the question, If 'D' value in PID is
changed, the process responds to the rate of change of
error between the PV & SP. In operation, controller first
compares current PV with the last PV value. If there is a
change in slope of PV, controller determines the output at
a future point in time. This future point in time
represents the derivative setting. Derivative mode
increases the output by that amount.
Advantage: Rapid o/p reduces time required to bring PV to
SP.
Disadvantage: Dramatically amplifies noise signals & can
cause cycling in fast process.

Answer / swatihendre

If D increased then output response will be fast and if D
decreased then output response will slow

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