What the 50 ms sampling buys you on a process line
The PXF9ACS2-MVMA1: That sampling rate means it catches fast thermal transients — injection molding nozzle temperature spikes, reflow oven zone overshoot, or extruder barrel swings — that a 100 ms or 200 ms controller would alias or miss entirely. Self-tuning here is the PID autotune that runs a relay-bump cycle on first power-up and sets the P, I, and D terms. On a thermal system with a long time constant (oven, kiln, heated bath) the autotune converges in a few cycles and the loop stays tight without manual tuning.