Bently Nevada 330105-02-12-05-02-01 3300 XL 8 mm Reverse Mount Probes

The Bently Nevada 330105-02-12-05-02-01 serves as the primary 330105 Reverse Mount Probes utilized to execute non-contacting shaft displacement and dynamic vibration measurements across 3500 Machinery Protection System platforms. The module operates via high-frequency eddy-current generation, translating physical proximity changes into corresponding electrical voltage variations when connected to a 3300 XL Proximitor Sensor.

Suffix Breakdown & Model Matrix

The complete model number options represent specific mechanical and certification parameters defined by the factory:

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

• 02: Unthreaded length option.

• 12: Overall case length option.

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

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

• 01: Agency Approval Option designating ATEX, IECEx, and CSA intrinsic safety and non-incendive certifications.

Hardware Specifications

Gap Voltage Validation and Eddy-Current Scaling

Mechanical calibration of the Bently Nevada 330105-02-12-05-02-01 requires rigorous gap voltage validation during field commission. The physical installation depth must be adjusted within the reverse mount housing until the static DC voltage across the Proximitor signal output measures a baseline -10 VDC target. This positions the target within the absolute center of the linear operational range, maintaining the standard eddy-current probe scaling factor of 7.87 V/mm. Operating inside this verified window prevents measurement saturation caused by extreme rotor dynamics and relies on structural cable shielding to ensure active cross-talk suppression when positioned adjacent to neighboring multi-channel machine monitoring components.

Frequently Asked Questions

Q: How does the Agency Approval Option 01 impact installation rules compared to Option 00?

A: Option 01 designates official hazardous area certifications. To maintain the intrinsic safety (Ex i) rating, the probe circuit must be routed through certified intrinsic safety barriers or galvanic isolators inside the control enclosure, complying strictly with maximum entity parameters ($V_{max}$, $I_{max}$).

Q: What physical protection prevents the ClickLoc connector from unlocking during high-frequency vibration?

A: The miniature ClickLoc coaxial connector features a specific internal detent mechanism that maintains contact tension. For harsh field environments, external connector silicone sleeves must be installed over the joint to provide mechanical reinforcement and prevent moisture ingress.

Field Installation Guidelines

• Reverse Mount Thread Alignment: Manually thread the 3/8-24 UNF housing into the probe sleeve to avoid cross-threading. Secure the locknut to the factory-specified torque to eliminate mechanical drift from rotor dynamics.

• Cable Bend Restrictions: Do not bend the integrated 0.5 metre coaxial cable sharper than a 25.4 mm (1.0 inch) minimum bend radius. Kinking or pulling the cable can distort internal impedance properties, causing false calibration drift.

• Junction Box Isolation: Terminate the ClickLoc connection inside a sealed, weatherproof junction box. Use terminal isolation blocks to ensure the coaxial shield layer does not inadvertently connect to the machine chassis ground at the installation point.

• Target Surface Condition: Verify that the targeted shaft surface area is free from mechanical scoring, chrome plating variances, or high residual magnetism, as these anomalies distort eddy-current fields and create false runout signals.