What the ratings mean for your BOM line
The Omron E2E-X3D2-M1G is a shielded DC 2-wire proximity switch with a 3 mm sensing distance and normally closed output. The NC configuration is the one that matters for fail-safe interlock circuits – a loss of power or sensor failure opens the contact, breaking the safety chain. The 3 mm range is the actual detection gap at the face; shielded construction lets you mount it flush in steel without derating. It connects via an M12 connector (IEC arrangement), which saves panel wiring time compared to pigtail models – just plug in a standard M12 cordset. The DC 2-wire output simplifies the circuit: one wire for power, one for signal, and it works with both PNP and NPN inputs on the PLC side (the sensor self-polars).