Sensor signal and fit
The Festo SMTO-4U-PS-S-LED-24 is a magneto-inductive proximity sensor in a U-shaped round housing, delivering a PNP normally-open switching output. It operates on a 10–30 V DC supply and switches up to 200 mA — typical for direct input to a PLC or a small relay load. The M8 3-pin connector keeps wiring consistent with Festo's SMTO/SMT sensor family; the IP67 rating means the sensor body and the M8 coupling withstand washdown, so it suits pneumatic actuator position feedback on a food-grade or wet-area line.
Peer contrast — connector vs. cable
The closest functional peer is the SMT-8F-PS-24V-K0,3-M8D, which uses a cable with an M8 plug rather than the SMTO-4U's pure M8 connector. Both are PNP normally open, 10–30 V DC, but the SMT-8F carries a 100 mA rating and a narrower temperature range (-5 to 60 °C). The SMTO-4U's 200 mA output and wider -25 to 70 °C range give it more headroom for higher inrush loads or hot cabinet environments.
Mounting and materials
The U-shaped round housing is PET, PA, and PUR — lightweight and corrosion-resistant for pneumatic cylinder T-slot mounting. Ambient operating temperature spans -25 to 70 °C, covering most cabinet and machine-mount conditions. The M8 connector locks with a standard 3-pin mating cordset; no special tooling needed for panel integration.