The Bently Nevada 330881-28-04-105-00-02, also cataloged as the 330881 PROXPAC XL Proximity Transducer, operates as a dedicated hardware component for integrated non-contacting vibration and position monitoring within 3300 XL series instrumentation platforms.

Suffix Configuration Matrix

The 330881-28-04-105-00-02 part number denotes a specific mechanical and electrical assembly configuration. This model features an 8 mm probe tip diameter with 3/8-24 UNF threads and a 10.5 meter integral cable length. The PROXPAC XL design integrates the Proximitor sensor functionality directly into the probe assembly, providing a consolidated solution for applications with limited internal space for standard two-piece transducer systems.

Hardware Specifications

Mechanical Monitoring & Transducer Scaling

The PROXPAC XL system utilizes eddy-current principle to measure relative shaft displacement. Precise rotor dynamics analysis requires the system to be operated within its linear range, calibrated to a -10 VDC gap voltage target. Cross-talk suppression is maintained by adhering to the minimum separation distance requirements defined in the installation documentation, ensuring that adjacent electromagnetic fields do not induce signal interference. The integrated circuitry is factory-calibrated to the 10.5 m cable length, and any alteration to the cable length will permanently impact the transducer's sensitivity and linear range.

Ordering & Shipment Contents

• 1x 330881-28-04-105-00-02 PROXPAC XL Transducer

• 1x Technical documentation package

• 1x Connector protective cover

• 1x Factory calibration verification sheet

Field Installation Guidelines

• Torque Specifications: Tighten the lock nut to 5.1 N-m (45 in-lb) to ensure structural stability without damaging threads.

• Cable Routing: Protect the 10.5 m integral cable from excessive pulling forces and maintain a minimum bend radius of 25 mm to prevent center conductor damage.

• Grounding: Secure the probe case to the machine structure; ensure electrical isolation from the mounting bracket only if required by specific plant grounding protocols.

• Alignment: Verify that the probe tip is perpendicular to the target surface to maintain accurate radial vibration and axial position measurement.

Frequently Asked Questions

• Can I field-shorten the integral cable? No, the PROXPAC XL is calibrated as a single, integrated assembly; modifying the cable length invalidates the factory scale factor.

• What is the maximum gap voltage? Nominal operation is -10 VDC; signal clipping typically occurs near -18 VDC to -20 VDC.

• Is the PROXPAC XL repairable? No, the unit is hermetically sealed to protect internal electronics and is not intended for field repair.

• Can I use this in an existing 3300 XL system? Yes, provided the system configuration matches the impedance and signal requirements of the PROXPAC XL design.

• How is the probe protected against chemical damage? The tip is constructed from PPS (polyphenylene sulfide), which is chemically resistant to standard industrial hydrocarbons.

• What is the effect of changing the target material? Calibration is based on 4140 steel; other materials will cause deviations in sensitivity and require system compensation.

• Does this device support hot-swapping? The assembly is wired directly into the instrumentation loop; power must be disconnected at the terminal block before removal.

• Is this transducer suitable for high-speed rotors? Yes, it is rated for typical industrial rotor dynamics, provided the mechanical mounting is secure and resonant-free.