The Siemens 3RG7408-7CH00 is a SIMATIC PXO370 C20 laser contrast sensor built for industrial presence detection where you need a tight spot and fast switching. DC 10-30V supply, PNP output, light-on/dark-on programmable, rated 100mA. Sensing range is 40 to 150 mm — useful for close-up mark or edge detection on a conveyor or packaging line. Housed in a 31x20x12 mm package with an M8 4-pole connector, sealed to IP67, so it shrugs off the dust and washdown that kill lesser sensors.
The 40-150 mm sensing range is the working window for the laser contrast detection — not a through-beam or retro-reflective distance. At 10-30 VDC the sensor accepts standard industrial supplies; the PNP output sinks 100 mA, enough to drive a PLC input or small relay directly. IP67 means the housing handles hose-down and dust, but the M8 connector needs a proper mating cordset rated for the same environment. The 31x20x12 mm body fits tight spaces on a machine frame or bracket.