Configured for radial and axial shaft displacement monitoring in Bently Nevada 3300 NSv series machinery protection systems, the Bently Nevada 330901-14-43-05-02-05 (330901 Proximity Probe) provides direct eddy-current proximity measurement for rotating machinery.

Suffix Breakdown & Model Matrix

Hardware Specifications

Eddy-Current Probe Scaling & Rotor Dynamics Compatibility

The 330901 NSv probe operates on the eddy-current principle, generating a high-frequency RF signal that induces eddy currents in the target conductive surface. The resulting impedance change is converted to a DC voltage proportional to the probe-to-target gap. Nominal scale factor is 200 mV/mil (7.87 V/mm) with a linear range extending to approximately 80 mils (2.03 mm) depending on target material and probe geometry. Gap voltage validation targets -10 VDC at the transducer output under standard calibration conditions. The extended 4.3 in case length and 1.4 in unthreaded section provide additional mounting flexibility for applications with complex rotor dynamics profiles, allowing the probe to be positioned deeper into bearing housings or behind obstructions. Cross-talk suppression is achieved through the coaxial ClickLoc connector design, which maintains signal integrity in electrically noisy environments typical of rotating machinery installations.

Ordering Info

• 1 x 330901-14-43-05-02-05 Proximity Probe (unarmored, 1.4 in unthreaded, 4.3 in case, 0.5 m cable, ClickLoc connector, Multiple Approvals)

Field Installation Guidelines

• Verify probe tip is free of debris and damage before installation.
• Engage a minimum of 5 full threads of the 1/4-28 UNF fitting into the probe bracket or housing.
• The 1.4 in unthreaded length allows axial adjustment; secure with locknut after setting the target gap.
• Ensure the probe tip does not contact the rotating shaft at any position throughout the full operating range.
• Route the coaxial cable away from high-voltage conductors and switching devices to minimize EMI.
• Terminate the cable shield at the signal conditioner end only (single-point ground) to prevent ground loops.
• Confirm the ClickLoc connector is fully seated and the locking mechanism is engaged.
• Verify agency approval markings are visible and match installation site requirements.

Frequently Asked Questions

• Q: What is the nominal gap voltage target for this probe during calibration?

  A: The standard gap voltage target is -10 VDC at the transducer output when the probe is positioned at the mid-scale gap distance from the target surface.

• Q: Can this probe be used with 3300 XL series extension cables?

  A: No. The 330901 NSv probe uses a miniature coaxial ClickLoc connector and is designed specifically for the 3300 NSv system. It is not compatible with 3300 XL extension cables.

• Q: What is the linear measurement range of the 330901 probe?

  A: The linear range is approximately 80 mils (2.03 mm) total, with a scale factor of 200 mV/mil. The usable range may vary slightly based on target material properties.

• Q: What is the significance of the 1.4 in unthreaded length?

  A: The unthreaded section allows the probe to be inserted deeper into the mounting hole past the threads, providing axial positioning flexibility without requiring additional spacers or adapters.

• Q: What target materials are compatible with this eddy-current probe?

  A: The probe is calibrated for ferrous and non-ferrous conductive materials. Standard calibration targets are 4140 steel. Different materials will produce different scale factors.

• Q: What does "Multiple Approvals" indicate for this probe?

  A: Multiple Approvals indicates the probe meets certification standards for installation in hazardous areas under various agency classifications. Verify specific approval codes against site requirements before installation.

• Q: What is the function of the ClickLoc connector locking mechanism?

  A: The ClickLoc connector provides a secure, vibration-resistant connection that prevents accidental disengagement due to machinery vibration. Always verify the lock is fully engaged after connection.

• Q: Can this probe be hot-swapped while the system is operational?

  A: No. The probe and its signal conditioner should be installed and wired with the system de-energized. Verify gap voltage and signal integrity after installation before returning to service.