The PXF4AEY2-FBKA1 is a self-tuning 1/16 DIN (48 x 48mm) compact temperature and process controller from Fuji Electric's PXF series.
What the 50 ms sampling means on the line
The 50ms sampling speed drives the PID loop update rate. For a plastic extrusion barrel or a reflow oven zone, that's fast enough to prevent overshoot on ramp-up and hold steady-state within a degree or two. If you're replacing an older controller with a slower sample time, expect tighter control — but also check that your thermocouple or RTD input matches the controller's input type, since the order code encodes that configuration.