Configured for displacement and vibration monitoring in industrial rotating machinery, the Bently Nevada 330881-28-10-100-03-02 (330881 Proximity Transducer) provides direct physical/electrical execution of non-contact shaft position sensing. This transducer system utilizes eddy-current induction to generate a voltage signal proportional to the gap between the probe tip and the target surface. It operates by converting high-frequency excitation into a calibrated output, enabling precise tracking of shaft displacement and radial vibration. The component integrates into established machine monitoring loops, maintaining high signal linearity and frequency response across demanding industrial operating environments.

Model Matrix & Configuration

The 330881-28-10-100-03-02 is defined by a specific factory configuration:

• 28: Total probe length (standard)

• 10: Unthreaded length

• 100: Overall case length

• 03: Connector type

• 02: Agency approval

Hardware Specifications

TSI & Mechanical Monitoring Characteristics

Eddy-current probe scaling is calibrated to ensure output linearity over the specified measurement range. During installation, gap voltage validation is mandatory; installers must target -10 VDC when the probe is positioned at the center of its linear range. Rotor dynamics analysis depends on this precise gap setting to accurately capture shaft centerline position and vibration vectors. To ensure signal integrity, cross-talk suppression techniques must be applied by maintaining sufficient spacing between adjacent probes to prevent frequency beat interference from overlapping excitation signals.

Ordering Info

• 330881 Proximity Transducer

• Technical installation manual

• Protective thread cover

• Standard mounting accessories not included

Field Installation Guidelines

• Gap Setting: Use a feeler gauge to establish the initial gap and confirm the output voltage with a multimeter at the monitor input terminals.

• Torque Application: Apply specified torque to the probe locknut to prevent loosening caused by machine casing vibration.

• Shielding: Ensure the coaxial cable is routed in dedicated conduit to minimize electromagnetic interference.

• Grounding: Verify electrical continuity between the transducer case and the machine ground to establish a stable signal reference.

• Target Verification: Confirm the target surface is free of non-conductive coatings or debris that could impede eddy-current propagation.

Frequently Asked Questions

• Q: Is this transducer system compatible with all 3300 series monitors?

• A: No, it must be used with monitor modules configured specifically for this transducer's frequency and scaling parameters.

• Q: What is the purpose of the -10 VDC gap target?

• A: It centers the probe within its linear range, ensuring that both positive and negative vibration excursions are captured without signal clipping.

• Q: Can I extend the coaxial cable length in the field?

• A: No, the system calibration is dependent on the integral cable length; modification will result in impedance changes and measurement errors.

• Q: How does the probe tip handle high temperatures?

• A: The PPS tip is designed for continuous operation up to 177 deg C, maintaining structural and electrical stability under thermal stress.

• Q: What is the primary cause of signal drift?

• A: Drift is typically caused by temperature changes, mechanical loosening of the probe, or surface degradation of the observed target.

• Q: How do I test the transducer for faults?

• A: Perform a static gap check and observe the raw output voltage for noise or discontinuities while the machine is at rest.

• Q: Can this be used for axial position measurement?

• A: Yes, it is suitable for both radial vibration and axial position (thrust) measurements, provided the mounting is rigid.

• Q: Does the transducer require separate power?

• A: No, it is powered through the coaxial cable by the associated monitoring system or Proximitor sensor.