Integrator’s brief
The Omron E3Z-T81K 2M is a through-beam photoelectric sensor set from the E3Z series, delivering a 15 m sensing distance with a PNP output on a 12-24 V DC supply. The set pairs a transmitter and receiver in a compact rectangular body (7 mm wide, 31 mm tall, 20 mm deep) with a 2 m prewired cable. IP67 seals it for washdown environments; CE marked. Switching mode is selectable – Light On or Dark On – via a control line. The PNP output sources up to 100 mA, suitable for direct connection to a sourcing PLC input. Response time is 1 msec, enough for high-speed part detection on conveyor or packaging lines. Minimum detectable object is 12 mm diameter opaque.
How it compares
Versus the E3Z-T81 (also PNP, 15 m, 2 m cable), the E3Z-T81K 2M is physically narrower: 7 mm vs 11 mm wide. If your existing bracket or mounting slot is keyed for an 11 mm body, the 7 mm part may require a spacer or adapter. All other specs – sensing distance, output type, response time, IP67 – match. Versus the E3Z-T61K 2M, the difference is output polarity: this part is PNP; the T61 is NPN. Choose based on your PLC input card – NPN sinking inputs need the T61. Physical dimensions, cable length, and sensing distance are identical.