The Autonics CR Proximity Sensor delivers versatile non-contact object detection, adjustable dielectric sensitivity, and robust environmental protection engineered specifically for bulk material handling, liquid level monitoring, plastic molding lines, and automated packaging systems.

Universal Material Sensing with the Autonics CR Proximity Sensor

Unlike inductive sensors that only register ferrous and non-ferrous metals, the Autonics CR Proximity Sensor utilizes advanced capacitive sensing principles to detect materials based on changes in dielectric capacitance. This allows the sensor to detect a comprehensive range of substances—including liquids, bulk plastic resins, glass, ceramics, wood, and granular food products—through non-metallic container walls, sight glasses, and plastic piping without requiring process intrusion.

The unit features a rear-mounted precision multi-turn sensitivity potentiometer, enabling machine technicians to fine-tune sensing thresholds easily. This allows the sensor to filter out outer plastic tank walls or sight tubes while cleanly triggering only on the targeted liquid or bulk material inside. Built with durable polybutylene terephthalate (PBT) sensing heads and oil-resistant cabling, the enclosure meets IP66 ingress protection standards to withstand moisture, dust, and continuous industrial ambient washdown spray.

Key Features and Engineering Advantages

• Universal Medium Detection: Detects virtually any substance with a dielectric constant greater than air, including water, oils, chemicals, grains, and plastics.
• Precision Sensitivity Potentiometer: Built-in adjustment trimmer permits precise sensitivity calibration to avoid false triggers through sight glasses and vessel walls.
• Non-Intrusive Level Monitoring: Mounts externally on non-metallic tanks and pipes to provide reliable high-level and low-level boundary alarms.
• Integrated Electrical Protection: Incorporates surge protection circuitry, reverse polarity protection (DC models), and output short-circuit suppression.
• High-Visibility Status Indication: Rear-mounted red operation LED provides instantaneous visual confirmation of output actuation during commissioning and walkthrough audits.

Technical Specifications

Industrial Applications and Process Integration

The Autonics CR Proximity Sensor provides non-contact material verification and boundary limit detection across automated systems, including:

• Bulk plastic resin hopper low-level and high-level alarms in injection molding plants.
• Non-contact liquid level sensing through transparent PVC and PFA chemical feed tubes.
• Automated packaging carton closure detection and clear glass bottle presence tracking.
• Grain, sugar, flour, and powder level verification in food and agricultural silos.

Frequently Asked Questions

How is sensitivity calibrated on the Autonics CR Proximity Sensor?
With the sensor installed in position and target material absent, the technician adjusts the rear potentiometer until the output LED turns off. When the material enters the target zone, the trimmer is fine-tuned until the LED illuminates cleanly, establishing an accurate hysteresis threshold that ignores surrounding bracket metal or container walls.

Can the sensor detect fluid levels through opaque plastic drums?
Yes. Because water and aqueous liquids possess a much higher dielectric constant (ε ≈ 80) than polyethylene or polypropylene container walls (ε ≈ 2.3), the sensor easily detects the presence of the fluid behind the container wall when calibrated appropriately.

What is the difference between CR18 and CR30 model variants?
The model prefix denotes the outer threaded barrel diameter. The CR18 uses an M18 body with an 8 mm sensing distance, ideal for tight cabinet brackets or narrow tubing, while the CR30 features a heavy-duty M30 body providing an extended 15 mm sensing envelope for bulk silos and hopper walls.