5 mm sensing, NPN-NO output
The Omron E2FQ-X5E1 is a proximity sensor with a 5 mm sensing range and an NPN-NO output configuration. This means it detects ferrous targets up to 5 mm away and switches the output high when a target is present — the NPN open-collector transistor sinks current to ground, which is the standard interface for many PLC digital input modules that expect a low-side switch.