The Siemens 3RG7400-7CH00 is a SIMATIC PXO310 K20 diffuse sensor in a compact 31x20x12 mm housing. It runs on DC 10-30V, outputs PNP at 100 mA, and has a 3 m sensing range. The M8 4-pole connector and IP67 rating make it a straightforward swap on a machine where the original sensor failed.
The 10-30V DC supply covers standard 24 VDC control panels. The PNP output is common for Siemens PLC inputs — no pull-up resistor needed. The 100 mA load capacity handles most small relays or PLC input cards directly. Light/dark-on programmable gives flexibility for different target materials. The M8 4-pole connector is a standard industrial sensor interface; verify your cable has the mating connector.