Bently Nevada 330878-90-CN 3300 XL 11 mm Proximitor Sensor

The Bently Nevada 330878-90-CN 3300 XL 11 mm Proximitor Sensor represents the gold standard in eddy current proximity transducer technology for critical machinery protection. As part of the advanced 3300 XL series, this sensor is engineered to provide precise, non-contact vibration and displacement measurements for the most demanding industrial applications .

Key Features and Performance

This 3300 XL Proximitor Sensor delivers a standardized output of 3.94 V/mm (100 mV/mil), making it fully compatible with Bently Nevada monitoring systems . The system operates across a 0 to 8 kHz frequency range, capturing both dynamic vibration and static position data with exceptional accuracy .

The 11 mm probe tip provides a significantly longer linear measurement range compared to standard 8 mm systems, with a linear range of 4 mm . This extended range is essential for applications requiring greater measurement travel, such as axial thrust position monitoring in turbines and compressors, differential expansion measurements on steam turbines, and piston rod position monitoring on reciprocating compressors .

Advanced Design and Durability

The 330878-90-CN features a slim, space-saving design that supports both high-density DIN-rail mounting and traditional panel configurations . Enhanced RFI/EMI immunity ensures stable operation even near high-frequency radio signals, and allows the sensor to achieve European CE certification without special installation considerations .

Field wiring is simplified with SpringLoc terminal strips, eliminating the need for special installation tools while providing secure, reliable connections . All system components utilize gold-plated brass ClickLoc connectors that lock securely in place to prevent loosening under vibration .

System Compatibility and Upgrade Path

The 3300 XL 11 mm system is designed as a direct replacement for legacy 7200 series 11 mm and 14 mm systems . When upgrading, all components—probe, extension cable, and Proximitor sensor—must be replaced with 3300 XL series components . The sensor is fully compatible with 3500 monitoring systems (requiring appropriate configuration software) and existing 3300 systems may require modification .

Applications

Axial (thrust) position measurement

Steam turbine ramp differential expansion

Reciprocating compressor piston rod position/drop

Tachometer and zero-speed measurement

Keyphasor® phase reference signals 

The Bently Nevada 330878-90-CN 3300 XL 11 mm Proximitor Sensor delivers the reliability, precision, and durability required for protecting critical rotating machinery across power generation, petrochemical, and industrial processing environments.