Description
Designed for advanced shaft vibration and axial position monitoring in critical rotating machinery, the Bently Nevada 330881-16-00-307-06-02 integrates a proximity probe and a Proximitor sensor into a single, robust, field-mountable assembly. This PROXPAC XL configuration simplifies installation by eliminating the need for separate extension cables and external sensor housings, providing direct-to-controller signal transmission. Engineered for harsh industrial environments, the assembly offers superior resistance to moisture, chemical exposure, and mechanical stress, ensuring continuous and highly accurate displacement measurements for steam turbines, gas turbines, compressors, and large pumps.
Features
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Integrated Assembly: Combines the proximity probe and the Proximitor sensor within a single protective housing to minimize field wiring complexity.
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High-Precision Measurement: Delivers non-contact, continuous static and dynamic displacement readings of rotating shafts.
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Enhanced Environmental Protection: Rugged housing protects internal electronics from moisture ingress, corrosive atmospheres, and mechanical impacts.
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Broad Compatibility: Fully compatible with Bently Nevada 3500 and 3300 monitoring systems for seamless diagnostic integration.
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Mechanical Integrity: Heavy-duty threaded configuration ensures secure, vibration-resistant mounting directly on machine casings.
Applications
- Radial vibration and axial thrust position tracking in utility steam turbines.
- Critical shaft displacement monitoring in high-pressure centrifugal compressors.
- Bearing oil film clearance and shaft keyphasor measurements in industrial generators.
- Structural vibration and casing expansion monitoring in heavy industrial machinery.
Technical Specifications
| Parameter |
Specification |
| Manufacturer |
Bently Nevada (Baker Hughes) |
| Model Series |
PROXPAC XL (330881 Series) |
| Transducer Type |
Integrated Proximity Transducer Assembly |
| Target Calibration |
AISI 4140 Steel (Standard) |
| Nominal Scale Factor |
-7.87 V/mm (-200 mV/mil) typically |
| Linear Range |
2.0 mm (80 mils) standard |
| Operating Temperature Range |
Probe: -51 degC to +177 degC; Housing Assembly: -35 degC to +85 degC |
| Country of Origin |
United States |
Empirical Engineering Insights
Alternative Models & Compatibility
The PROXPAC XL series functions as an all-in-one replacement for discrete 3300 XL 8mm probes, matching their performance but integrating the sensor electronics into the junction box. When upgrading from older non-XL PROXPAC variants, ensure your field monitor configuration is updated to handle the electrical specifications of the 3300 XL series to avoid scale factor discrepancies.
Application Pitfalls & Engineering Notes
Target material selection is critical. This transducer is calibrated for AISI 4140 steel. Operating the sensor against other metals (such as stainless steel or chrome-plated surfaces) without recalibration will cause severe measurement errors and non-linear outputs. Additionally, ensure that the ambient temperature inside the junction enclosure does not exceed +85 degC during peak machine operation.
Commissioning & Wiring Tips
Always use high-quality, double-shielded twisted-pair cable for the field wiring from the PROXPAC terminal block to the monitor cabinet. The shield must be grounded at the monitor end only. Grounding the shield at both ends introduces ground loops that corrupt the high-frequency proximity signals with electrical noise.
Installation Guidelines
CRITICAL WARNING: Ensure the machinery is fully shut down and de-energized before beginning installation or adjustment of the PROXPAC transducer. High-voltage transients or accidental machinery startup during probe gapping poses extreme hazards to personnel and equipment.
1
Mount the PROXPAC XL housing securely to the machine casing, ensuring proper alignment with the target observation shaft.
2
Route field cables through the designated conduit entries on the housing using liquid-tight glands to protect against moisture.
3
Terminate field wiring inside the housing junction box. Ensure all terminal connections are tightened to specification to prevent signal attenuation.
4
Verify probe gapping voltage using a digital multimeter at the monitoring terminal prior to commissioning the machine.