The Bently Nevada 330105-02-12-05-02-01, also cataloged as the 330105 8 mm Reverse Mount Proximity Probe, is designed for internal machine mounting where space is limited and the probe must be secured from the inside of the machine case.

Suffix Breakdown & Model Matrix

The 330105-02-12-05-02-01 follows the standard Bently Nevada 3300 XL 8 mm system nomenclature for reverse-mount applications:

• 330105: 8 mm reverse mount proximity probe.

• 02: Unthreaded length (20 mm).

• 12: Overall case length (120 mm).

• 05: Total system length (0.5 meters).

• 02: Connector type (Connector without housing).

• 01: Agency approval (CSA/NRTL/C).

Hardware Specifications

Eddy-Current Sensing and Rotor Dynamics

This transducer system is optimized for applications where the probe must be installed through the interior of the machine case. It utilizes the eddy-current principle to measure shaft vibration and displacement. Like all 3300 XL systems, accurate scaling is required during commissioning; the target operational setpoint is -10 VDC at the monitor input to ensure the transducer operates within its linear sensing range. The architecture includes internal cross-talk suppression to maintain signal integrity in multi-channel TSI configurations.

Ordering info

• One (1) 330105-02-12-05-02-01 Reverse Mount Proximity Probe.

• Mounting hardware (nut and lock washer).

• Technical compliance documentation (CSA/NRTL/C certified).

• Note: Extension cables and Proximitor sensors must be impedance-matched to the 3300 XL 8 mm system.

Field Installation Guidelines

• Mechanical Interface: Insert the probe through the mounting hole from the inside of the case; secure using the provided nut and lock washer to ensure the probe remains rigid against the casing.

• Gap Setting: Establish the mechanical gap using a depth micrometer; verify the output voltage at the Proximitor test point (Target: -10 VDC).

• Cabling: Route the lead carefully to avoid sharp edges on the interior of the machine casing; use protective conduit if necessary.

• Connector Engagement: Ensure click-loc connectors are fully seated; a positive click must be felt to confirm electrical continuity and shielding integrity.

• Vibration Locking: Ensure the mounting nut is torqued correctly; the reverse-mount orientation relies on the integrity of the casing wall for structural stability.

Frequently Asked Questions

• Why is the "reverse mount" configuration used?

  Reverse mounting is required when there is insufficient external clearance to install a standard probe, or when the probe must be mounted inside an oil-filled bearing cavity.

• Does this probe require a matched extension cable?

  Yes. The 3300 XL system is calibrated as a set (Probe + Extension Cable + Proximitor); changing components requires verifying system-wide calibration.

• Can I use this probe in a hazardous area?

  The "01" suffix indicates CSA/NRTL/C agency approval; verify that your specific site hazardous area requirements are met by this classification.

• What is the target gap voltage for this model?

  The target gap voltage is -10 VDC, which positions the probe in the center of its linear range for optimal vibration measurement accuracy.

• Can the probe tip be repaired if damaged?

  No. The probe tip is permanently sealed; any damage to the tip or body requires replacing the entire probe assembly.

• Is the probe affected by target material variations?

  Yes. The transducer is calibrated for 4140 steel. If the target material differs, an adjustment to the scale factor is required to prevent measurement errors.

• How is a damaged cable identified?

  Damage typically results in a "Gap Error" signal on the monitor, caused by open or short circuits that drive the voltage outside the -10 VDC nominal target.