Omron E3T-ST11 2M Ultracompact Photoelectric Sensor

Technical Overview

The Omron E3T-ST11 2M is an ultracompact, built-in amplifier photoelectric sensor designed for reliable through-beam object detection in tight industrial spaces. It features a 1-meter sensing distance, a visible red LED (650 nm) light source for easy alignment, and an NPN open-collector output operating in Light-ON mode. Encased in an IP67-rated PBT housing, it provides excellent resistance to dust and water ingress. With a rapid 1 ms response time and standard M2 mounting, this pre-wired (2m) sensor is optimized for high-speed dynamic applications requiring a miniature footprint.

Key Features

Ultracompact and ultrathin profile with standard M2 mounting for space-constrained installations.
Through-beam detection technology achieving a 1-meter sensing distance.
Fast 1 ms maximum response time suitable for high-speed automated lines.
High-visibility red LED (650 nm) for straightforward optical alignment.
Durable IP67-rated PBT housing ensures operation in harsh, wet, or dusty environments.
Pre-wired with a 2-meter cable for direct and reliable electrical connection.
NPN open-collector output with Light-ON operation mode.

Technical Specification Matrix

Parameter	Value
Sensor Type	Through-beam (Emitter and Receiver)
Sensing Distance	1 m
Output Configuration	NPN
Switching Mode	Light-ON
Response Time	1 ms max.
Supply Voltage	12 to 24 VDC
Light Source	Red LED (650 nm)
Connection Method	Pre-wired (2 m)
IP Rating	IP67
Operating Temperature	-25 °C to 55 °C
Housing Material	PBT
Dimensions (W x D)	9.5 mm x 7.0 mm
Mounting Type	M2

Industrial Applications

1. Semiconductor Wafer and Lead Frame Detection

Utilized in tight semiconductor handling equipment to precisely detect the presence of thin wafers or metallic lead frames during transfer operations.

Problem Solved

Standard sensors are too bulky for the confined spaces of micro-handling robotics. The 9.5x7mm miniature profile and M2 mounting of the sensor allow non-intrusive installation without compromising the 1ms rapid detection needed for continuous motion control.

Ultracompact profileM2 mounting1 ms response timeThrough-beam

2. High-Speed Small Parts Counting

Integrated into the gravity chutes of pharmaceutical or electronic packaging machinery to count small pills or components as they drop into packaging containers.

Problem Solved

Small, fast-moving items can pass undetected by slower sensors. The high-visibility 650 nm red LED beam and ultra-fast 1 ms response time ensure that any tiny object breaking the 1-meter sensing path is accurately registered by the NPN output.

1 ms response timeRed LED (650 nm)Light-ON NPN1m sensing distance

3. Automated Robotic Assembly Verification

Deployed in robotic pick-and-place cells to verify the correct seating of sub-assemblies before a robotic arm proceeds with the next manufacturing step.

Problem Solved

Robotic cells often expose sensors to mechanical vibrations, dust, and sporadic fluid splashes. The IP67-rated PBT housing combined with the flexible 2-meter pre-wired connection ensures reliable, long-term operation under harsh environmental stresses.

IP67 ratingPBT housingPre-wired 2m12 to 24 VDC