E3T-SL21 OMRON Sensor
Key Specifications

• Sensing Type: Limited-reflective (diffuse limited reflective) 
• Sensing Distance: 5 mm to 30 mm (optimized for short-range detection)
• Light Source: Polarity-free red light 
• Output Type: NPN output, 3-wire DC 
• Operation Mode: Light-ON 
• Power Supply: 12 to 24 VDC 
• Response Time: 1 ms 
• Housing Material: PBT plastic with cuboid shape (approx. 7 mm width, 24.5 mm height, 11 mm depth) 
• Protection Rating: IP67 (dust and waterproof) 
• Connection: Fixed cable (typically 2 meters for standard E3T-SL21 2M variants)