For this challenge, assume that increasing the Output (OP) causes the Process Variable (PV) to rise. The Proportional and Derivative are configured to react on the Error.
The symbols ΔP, ΔI, and ΔD represent the current incremental contributions of the Proportional, Integral, and Derivative components, respectively. These incremental values are summed and added to the overall OP on each scan (update cycle).
The left side of the trend shows older process samples, while the right side reflects the most recent values. Each dot represents a sample value used by the PID algorithm to update the Output. The derivative term uses the most recent 3 samples.
Based on the trend, determine the sign of each incremental PID term. The following are the options to choose from:
Legend: