Bently Nevada 330105-02-12-05-02-00 3300 XL 8 mm Reverse Mount Probes

The Bently Nevada 330105-02-12-05-02-00, also cataloged as the 330105 Reverse Mount Probes, operates as a dedicated hardware component for non-contacting displacement and vibration measurement within 3500 Machinery Protection System platforms. It translates the physical gap distance between the probe tip and the target rotating shaft into a high-frequency eddy-current signal for proximity transmitter evaluation.

Suffix Breakdown & Model Matrix

The complete model nomenclature breakdown for this configuration is defined as follows:

• 330105: Base model for 3300 XL 8 mm Reverse Mount Probe (3/8-24 UNF thread).

• 02: Specifies the unthreaded length option.

• 12: Specifies the overall case length option.

• 05: Total Length Option designating 0.5 metre (1.6 feet) of integrated cable.

• 02: Connector Option designating a miniature ClickLoc coaxial connector.

• 00: Agency Approval Option designating not required.

Hardware Specifications

Gap Voltage Validation and Eddy-Current Scaling

Proper mechanical installation relies on absolute gap voltage validation during static positioning. Technicians must adjust the mechanical insert depth of the reverse mount probe housing to achieve a targeted -10 VDC output at the Proximitor terminal block layer, placing the sensor at the exact midpoint of its calibrated linear range. This alignment satisfies standard eddy-current probe scaling metrics, ensuring a linear conversion scale factor of 7.87 V/mm (200 mV/mil) is maintained across the measuring envelope. Precise physical gapping isolates the system from cross-talk suppression failures and guarantees the accurate tracking of high-frequency rotor dynamics without physical interface contact.

Frequently Asked Questions

Q: How is the physical continuity and signal shielding maintained at the ClickLoc joint?

A: The miniature ClickLoc coaxial connector utilizes a positive-lock mechanical collar that ensures constant physical electrical contact. Ground isolation must be managed via external connector sleeves to prevent external electromagnetic noise injection into the sensor loop circuit.

Q: Is hot-swapping or disconnect of the probe allowed while the Proximitor is energized?

A: Yes, the probe can be physically disconnected from the extension cable or Proximitor while powered. However, this action breaks the signal loop, causing the Proximitor output voltage to clamp to its maximum saturation limit, which will trigger an immediate NOT OK status fault on the associated monitor card.

Field Installation Guidelines

• Reverse Mount Mechanical Positioning: Thread the probe assembly carefully into the reverse mount housing or sleeve adapter. Avoid over-torqueing the 3/8-24 UNF thread structure to prevent deformation of the sensor tip internal core.

• Coaxial Routing Restrictions: Route the 0.5 metre integrated cable through approved non-conductive sleeves or flexible conduit blocks. Maintain a minimum mechanical bend radius of 25.4 mm to prevent inner-conductor shielding cracks.

• Electrical Ground Separation: Ensure the coaxial shield layer is isolated from the physical machine casing. Grounding must occur at exactly one point, terminated at the instrument rack or junction box common bus terminal.

• Target Calibration Area: Ensure the area directly under the 8 mm probe tip is free from surface scratches, plating irregularities, or localized magnetism to avoid generating artificial electrical runout errors.