Description

Technical Overview

The Bently Nevada 330881-28-05-035-01-02 Proxpac XL Proximity Transducer is a high-precision, industrial-grade eddy-current proximity sensing solution engineered for mission-critical machinery protection and condition monitoring systems. Manufactured by Baker Hughes (formerly Bently Nevada), a global leader in asset reliability and predictive maintenance technologies, this transducer forms the foundational sensing element of the renowned 3300 XL series—renowned for exceptional stability, wide temperature tolerance, and immunity to electromagnetic interference (EMI). Designed specifically for integration with Bently Nevada 3300/3500 monitoring systems, the 330881-28-05-035-01-02 delivers highly linear, repeatable displacement measurements of rotating shafts, thrust collars, and other ferromagnetic targets under extreme operational conditions. Its robust stainless steel housing, hermetically sealed construction, and optimized coil geometry ensure long-term calibration integrity across thermal cycles from –40 °C to +125 °C ambient. The transducer operates on a standard 18–30 VDC excitation supply and outputs a calibrated –2 to –18 VDC signal proportional to target gap, with a sensitivity of 7.87 V/mm (200 mV/mil) — fully compliant with API 670 (4th Edition) requirements for vibration and position monitoring in turbomachinery. Each unit undergoes rigorous factory calibration against NIST-traceable standards and is supplied with individual calibration certificate (Cal Cert) documenting linearity error (<±0.5% FS), frequency response (DC to 10 kHz), and thermal drift characteristics. This model is new, factory-fresh inventory—never installed or refurbished—and carries a full 24-month limited warranty covering material defects and workmanship.

Detailed Specifications

Key Features

• Ultra-High Stability Calibration: Patented XL coil design minimizes thermal hysteresis and ensures <±0.3% zero shift over 10,000 thermal cycles — critical for long-term unattended operation in power generation and oil & gas facilities.
• Hermetic Ceramic-to-Metal Seal: Eliminates internal moisture ingress and prevents dielectric breakdown, extending service life beyond 20 years in harsh, high-humidity environments such as offshore platforms and pulp & paper mills.
• Integrated Cable Strain Relief: Reinforced PTFE jacket and molded boot provide IP68-rated ingress protection and withstand >200 N axial pull force — reducing field failure due to cable fatigue or mishandling.
• API 670-Compliant Output Architecture: Delivers true DC-coupled displacement data with no high-pass filtering artifacts, enabling accurate measurement of shaft static position (e.g., thrust bearing wear, rotor centering) alongside dynamic vibration.
• Plug-and-Play Compatibility: Fully interoperable with Bently Nevada 3300/3500/3600 monitoring systems, System 1™ software, and third-party DCS/PLC interfaces via standard 4–20 mA or voltage input modules.
• NIST-Traceable Calibration Documentation: Each unit ships with a unique serial-numbered calibration certificate listing actual sensitivity, linearity deviation, thermal coefficients, and traceability to National Institute of Standards and Technology standards.
• Optimized for High-Speed Turbomachinery: Validated performance up to 30,000 RPM with minimal phase lag (<1° at 5 kHz), making it ideal for compressor trains, steam/gas turbines, and high-speed motors.

Applications

• Turbine Monitoring: Real-time shaft axial position (thrust), differential expansion, and casing relative movement in steam, gas, and hydroelectric turbines per API 612 and ISO 10816 standards.
• Compressor Protection: Detection of surge onset, bearing wear progression, and rotor instability in centrifugal and reciprocating compressors deployed in petrochemical refineries and LNG facilities.
• Generator & Motor Health Assessment: Measurement of air gap eccentricity, rotor bar faults, and magnetic center shift in large synchronous and induction machines (>5 MW).
• Aerospace Ground Test Stands: High-fidelity transient displacement capture during engine run-up, spin testing, and modal analysis where sub-micron resolution and phase accuracy are mandatory.
• Industrial Gearbox Diagnostics: Monitoring gear mesh deflection, bearing preload loss, and housing distortion in mining, cement, and marine propulsion systems.
• Research & Development Labs: Precision motion control feedback, material property characterization (e.g., thermal expansion coefficient), and calibration reference instrumentation in metrology laboratories.