Sensing distance and shielding
The Omron E2EL-C2ME1-M3 is an unshielded proximity sensor with a 2 mm sensing distance. Unshielded means the field projects further from the face than a shielded equivalent, but it also means the sensor needs more clearance from surrounding metal — mount it with at least three times the sensing distance (6 mm) of free space around the barrel to avoid false triggers.
Output and wiring
Output is NPN normally open — the load switches on when metal enters the 2 mm detection zone. The M8 3-pin connector mates with standard M8 cordsets; pin 1 is brown (Vcc), pin 4 is black (NPN output), pin 3 is blue (GND). No pull-up resistor needed if the PLC input is sourcing type.