Optimal PID Settings for Varying Loops

This new loop summary table is designed to find the best PID settings to use for loops that behave differently with varying conditions. Users can perform several tests on a loop and the table summarizes the results. For each test, the table lists the tuning parameters, process model, model confidence, and relative response time for the loop. The table automatically highlights the most conservative and the average tuning values. The most conservative tuning values are useful in loops with varying conditions, e.g., temperature loops that heat up quicker than they cool down. They may be the only tuning values that are stable.

The table saves the process model so users can compare the process model today with the process model from a previous ExperTune test. This gives a historical perspective, aiding in troubleshooting.

The relative response time calculation is a measure of the time the loop takes to correct a disturbance. Use it to decouple interacting loops. Faster loops should be tuned to have an RRT at least 3 times smaller than slower loops. Users can then be sure that the faster loop will correct a disturbance before it has much effect on the slower loop.

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