Sensor selection guide for Conveyor application

Choosing the right sensor for your conveyor system ensures optimal efficiency, safety, and automation. Below is a practical guide structured by function, environment, and use case—complete with real-world considerations and engineering tips.

1. Object Detection and Counting

Application	Recommended Sensor Type	Why
Detect box or product on belt	Photoelectric (diffuse or retro-reflective)	Fast and reliable for detecting standard objects on a moving line
Transparent or irregular objects	Ultrasonic or Through-beam Photoelectric	Capable of detecting glass, shrink wrap, and non-reflective surfaces
Small metal parts	Inductive Proximity Sensor	Durable and accurate for close-range metallic detection
Food or non-metallic packages	Capacitive Proximity Sensor	Detects moist or organic packages like bakery goods or produce

2. Conveyor Belt Monitoring

Function	Recommended Sensor Type	Why
Monitor belt speed	Encoder or Tachometer	Feedback for speed regulation and VFD synchronization
Detect belt misalignment	Belt Sway Sensor or Limit Switch	Safety mechanism to prevent belt drift or spillage
Detect belt tear or rip	Cable-pull or Inductive Tear Sensor	Stops operation upon mechanical failure
Belt overload protection	Load Cell or Weighing Sensor	Prevents motor strain and material pile-up

3. Motor and Drive Health Monitoring

Function	Sensor Type	Why
Motor shaft speed	Rotary Encoder	Enables precision feedback to motor control systems
Motor or bearing temp.	RTD or Thermocouple	Early detection of overheating, ideal for predictive maintenance programs
Abnormal vibration	Piezoelectric Vibration Sensor	Identifies imbalance or bearing wear in rotating equipment

4. Position and Limit Control

Application	Sensor Type	Why
Detect end-of-travel	Limit Switch or Proximity Sensor	Simple and robust endpoint detection
Position of diverters/flaps	Inductive Proximity Sensor	Immune to dust and wear from repetitive mechanical operations
Conveyor inclination angle	Tilt or Inclinometer Sensor	For safety interlocks in steep incline conveyors

5. Sorting, Tracking, and Identification

Application	Sensor Type	Why
Barcode scanning	Laser Barcode Scanner or Imager	Tracks inventory and automation in logistics systems
Product identification	RFID Reader	Enables wireless ID of tagged pallets, bins, or totes
Visual inspection	Vision Sensor or Smart Camera	Detects defects, validates orientation, counts irregular items

Add smart cameras if you need multiple object checks like label presence, cap closure, or shape detection.

6. Environmental Conditions for Sensor Selection

Condition	Sensor Feature Needed	Recommended Sensor Type
Dusty / harsh environment	IP65/IP67 rating, sealed optics	Inductive, Ultrasonic, or Sealed Photoelectric
Hygienic / food industry	FDA-compliant, stainless housing	IP69K-rated Capacitive or Photoelectric sensors
Wide temp or outdoor use	Broad operating range (-25°C to 70°C)	Rugged Industrial-grade Proximity or Encoders

Industry Reference: Refer to IEC 60529 standards when selecting IP-rated sensors for washdown or dusty conditions.

Quick Reference Chart

Function	Best Sensor Options
Product Presence	Photoelectric, Capacitive, Ultrasonic
Speed Monitoring	Encoder, Tachometer
Position / Limit Sensing	Limit Switch, Proximity Sensor
Weight Detection	Load Cell
Tracking / Sorting	Barcode, RFID
Condition Monitoring	Temperature, Vibration
Belt Damage Protection	Belt Sway, Tear Detector