Product Overview

The 330780-91-00 is a high-performance signal conditioning unit designed for the Bently Nevada 3300 XL 11 mm Proximity Transducer System. This Proximitor sensor converts the radio frequency (RF) signal from a non-contacting probe into a linear voltage output proportional to the gap between the probe tip and the target. Engineered for large-scale machinery, the 11 mm system provides a significantly larger linear range than standard 8 mm sensors, making it essential for applications involving significant shaft thermal expansion or wide axial thrust monitoring. This specific model is factory-calibrated for a 9.0-meter total system length, allowing for extended cable runs between the machine and the monitoring rack.

Technical Performance and Electrical Specifications

The 330780-91-00 is designed for high-fidelity data acquisition in demanding Turbine Supervisory Instrumentation (TSI) environments:

• Linear Range: Provides an extended 4.0 mm (160 mil) linear measurement range.

• Scale Factor: Delivers an average scale factor of 3.94 V/mm (100 mV/mil).

• System Configuration: Calibrated for a 9.0-meter (29.5 feet) total length (91 option).

• Power Input: Operates between -17.5 Vdc to -26 Vdc (barrier-free) or -23 Vdc to -26 Vdc (with barriers), with a maximum current draw of 12 mA.

• Signal Stability: Exceptional voltage regulation with less than 2 mV output change per volt of input variation.

• EMI/RFI Immunity: Advanced shielding exceeds European CE standards, ensuring signal integrity in electrically noisy industrial sites.

Engineering Design and Field Integration

Built to withstand the rigors of power generation and petrochemical facilities, the sensor incorporates several mechanical innovations:

• High-Density Mounting: The slim, compact profile (8.8 x 3.6 x 7.1 cm) supports 35 mm DIN-rail or traditional bulkhead installation, maximizing cabinet space efficiency.

• SpringLoc Terminal Strips: Features tool-free, vibration-resistant wiring terminals that simplify field connections and prevent wire loosening in high-vibration areas.

• Environmental Durability: Robust construction designed for long-term service in harsh industrial conditions where moisture and temperature fluctuations are common.

• Standard Approval: The -00 suffix indicates the standard non-hazardous area version, offering a cost-effective solution for general industrial applications.

Primary Industrial Applications

The 11 mm 330780-91-00 Proximitor is a critical component for protecting high-capital rotating assets, including:

• Large Steam and Gas Turbines: Monitoring axial thrust position where wide thermal expansion is expected.

• Hydroelectric Generators: Tracking radial vibration and shaft centerline position on large-diameter units.

• High-Power Pumps and Compressors: Providing early fault detection for imbalances, misalignments, and bearing degradation.

• Keyphasor Signals: Generating clean, stable phase reference pulses for machinery balancing and advanced rotor dynamic diagnostics.