Product Overview

The Bently Nevada 330104-06-25-05-02-00 is a premium industrial 3300 XL 8 mm Proximity Probe designed for absolute precision in machinery protection and condition monitoring systems. Operating on the eddy current transducer principle, this non-contacting displacement sensor provides high-resolution data regarding radial shaft vibration, axial thrust positioning, and phase reference (Keyphasor) telemetry. It is universally trusted across heavy process industries to track high-speed rotor dynamics inside critical fluid-film bearing housings.

The 3300 XL 8 mm probe series offers a dependable linear measurement range of 2.0 mm (80 mils). It excels at maintaining an exceptionally flat thermal response line across fluctuating internal machinery temperatures, providing excellent repeatability where minor deviations could trip a multi-megawatt asset.

This specific English-threaded hardware layout is configured with a 3/8-24 UNF threaded body featuring a 0.6-inch unthreaded section, a 2.5-inch overall case length, a short 0.5-meter (1.6 feet) integrated coaxial cable without armor, and a miniature coaxial ClickLoc connector. Carrying the standard "No Approvals" designation, this probe option balances procurement budgets when replacing components in general-purpose safe areas, non-hazardous zones, or internally isolated instrument enclosures.

Technical Specifications

Model Configuration Explanation

The model string 330104-06-25-05-02-00 represents a precise selection from the Bently Nevada 3300 XL 8 mm catalog, mapping out the physical parameters required for exact mechanical field drop-ins:

• 330104: The foundational base model number for the 3300 XL 8 mm Proximity Probe configured with an English thread profile (3/8-24 UNF).
• 06: Unthreaded Length Option. Specifies a 0.6-inch unthreaded sleeve behind the probe tip. This design provides clean clearance inside mounting blocks or specialized sleeve adaptors.
• 25: Overall Case Length Option. Designates a 2.5-inch total case length, giving the sensor structural body depth to pass through average machinery housing interfaces.
• 05: Total Length Option. Dictates a 0.5-meter (1.6 feet) integrated cable lead. This short length is engineered to connect cleanly to internal bulkheads or local junction boxes positioned immediately adjacent to the bearing cap.
• 02: Connector and Cable Type Option. Selects a standard miniature coaxial ClickLoc connector with unarmored cable insulation. This option offers excellent routing flexibility when installing through dedicated protective conduits.
• 00: Agency Approval Option. Specifies the "No Approvals" configuration. This config is tailored specifically for plant operations inside safe areas, avoiding regulatory premiums where explosion-proof stamps are unnecessary.

Typical Applications

The 330104-06-25-05-02-00 proximity probe is critical for assessing machine health across continuous process industries, particularly where standard unarmored leads are protected by rigid field conduit piping:

• Centrifugal Gas Compressors: Non-contacting tracking of high-speed oil-film bearing vibration profiles and phase angle references.
• Boiler Feed Water Pumps: Monitoring rotor axial position and thermal thrust displacement under intensive industrial utility loads.
• Induced Draft (ID) & Forced Draft (FD) Fans: Continuous vibration protection for large scale air handling setups inside chemical and manufacturing complexes.
• Steam Turbine Generators: Providing accurate shaft orbit readings and diagnostic keyphasor tracking to protect sub-components during critical startup speeds.
• Industrial Cooling Systems: Mounted directly on gearbox shafts to guard against sudden misalignment or mechanical bearing degradation.

System Compatibility

To satisfy rigorous API 670 operational design parameters, the 330104 proximity probe must be matched with its complementary signal conditioning components to complete the circuit loop:

• Extension Cable Selection: Must be paired with a 3300 XL 8 mm Extension Cable (such as the 330130 series). Because the integrated probe cable length is 0.5 meters, it must be paired with either a 4.5-meter or 8.5-meter extension cable to establish a true 5.0-meter or 9.0-meter total system tuning loop.
• Proximitor Sensor Integration: Connects directly into a matching 3300 XL Proximitor Sensor (Model 330180). The Proximitor converts high-frequency eddy current impedance into a linear -24 Vdc voltage representation.
• Protection Monitors: Seamlessly links terminal blocks directly to the backplane inputs of the Bently Nevada 3500/42M Proximitor Seismic Monitor module or classic standalone 3300 vibration controllers.

Mechanical Position & Gapping Guidelines

• Shaft Surface Treatment: Ensure the shaft measurement path is completely free of grinding patterns, score marks, or metallurgic variations. A surface finish of 0.8 micrometers (32 microinches) Ra or better prevents artificial electrical runout signals.
• Setting the Operating Gap: Thread the probe into its mounting bracket while checking the DC bias voltage at the Proximitor Sensor's terminal strip or buffered output port. Turn the body until the meter shows -10.0 Vdc, marking the precise midpoint of the 2.0 mm linear tracking envelope.
• Adjacent Metal Clearance: Maintain a clear hole or counterbore diameter of at least 30 mm (1.2 inches) surrounding the exposed 8 mm probe tip. Inadequate radial clearance causes the probe to sense the edges of the bracket, shifting the true scale factor.
• Cross-Talk Elimination: When installing two sensors in an X-Y configuration on the same bearing face, separate the probe tips by a minimum of 40 mm (1.6 inches). This prevents overlapping RF fields from causing cross-talk noise interference.
• Torque and Locking Safety: Once the -10.0 Vdc gap voltage is confirmed, secure the position by tightening the 3/8-24 UNF hex locknut. Do not exceed the structural limit of 11.2 N·m (100 in·lb). Run lockwire through the predrilled nut holes to secure the assembly against continuous shaft frequency vibration.

Product Advantages

• Excellent Thermal Performance: Designed to exhibit minimal scale factor drift across its full temperature operating profile, ensuring true measurements during extreme turbine startups.
• Tool-Less ClickLoc Connectors: Features gold-plated brass coaxial connectors that engage with a positive click. This design resists terminal corrosion and vibration detachment without requiring special crimping tools.
• Robust Mechanical Design: Built using proprietary TipLoc molding to chemically fuse the ceramic tip to the stainless steel body casing, complemented by CableLoc design offering 330 N of continuous wire pull-strength relief.
• Maximum Routing Flexibility: The unarmored cable option provides a tight bend radius, allowing for smooth, zero-resistance routing paths inside tight internal machine cavities or dedicated external conduit junctions.
• Hot-Swap Capability: Manufacturing standards allow the probe, cable, or Proximitor sensor to be replaced independently without requiring any field calibration.

Ordering Information

Procurement Note: When ordering this 0.5-meter probe configuration for maintenance replacement, confirm whether your underlying loop design is a 5-meter or 9-meter layout. This ensures you acquire the exact 4.5m or 8.5m extension cable required to preserve system calibration.

Logistics and Shipping

To preserve precision hardware calibration during global transport, all products are handled with industry-standard instrument packing steps:

Professional Packaging Protocol:

Every Bently Nevada 330104 probe is sealed inside an anti-static industrial packaging shield to isolate the internal eddy-current components from static discharge hazards. The sensor head and its flexible unarmored cable are cradled within custom-cut, high-density shock protection foam liners inside a heavy-walled corrugated structural shell. This eliminates the risk of impact crimping, connector flattening, or drop damage during long-distance international air or sea cargo shipping.

Frequently Asked Questions

• Can I use a 330104-06-25-05-02-00 probe with a 5.0-meter extension cable?

  No. Because this probe has an integrated 0.5-meter cable lead, it must be paired with either a 4.5-meter extension cable (to form a 5.0m system) or an 8.5-meter extension cable (to form a 9.0m system). Using a 5.0-meter extension cable will cause a total loop length mismatch, destroying measurement accuracy.

• What does the "06" configuration value indicate?

  The "06" value means the probe has a 0.6-inch long unthreaded section behind the tip. This is useful when inserting the probe through tight-fitting mounting blocks where threads could binding or scratch internal clearances.

• What is the standard output scale factor of this proximity sensor loop?

  The nominal scale factor is 7.87 V/mm (200 mV/mil). A physical movement of 1 mil (0.001 inches) by the rotating shaft translates into a clean, measurable 200 mV shift in the DC output voltage signal.

• Why choose the unarmored cable option ("02") over an armored option?

  The unarmored option is highly flexible and has a significantly smaller outer diameter. It is ideal for routing through existing flexible conduits, tight bends, or internal machine paths where bulky stainless steel armor would jam or add unnecessary weight.

• How can I identify a probe circuit failure using a digital voltmeter?

  Measure the DC voltage across the Proximitor Sensor's output terminals. A reading near 0 Vdc points to a shorted line or connector fault. A reading hitting -24 Vdc indicates an open loop, a cut cable, or a probe tip located far outside its linear measurement envelope.

• Does this probe require routine bench calibration before field deployment?

  No. The entire Bently Nevada 3300 XL platform is built with full component interchangeability. As long as you match an 8 mm probe with an 8 mm extension cable and an 8 mm Proximitor sensor within the correct total loop length, the loop self-calibrates to factory specs.

• What shaft material is this probe factory-calibrated to measure?

  The standard calibration target material is AISI 4140 electric steel. If your asset's shaft is made of high-chrome alloys, stainless steel, or aluminum, custom calibration or software correction factor adjustments are necessary to ensure accuracy.

• Is the 330104-06-25-05-02-00 certified for use in hazardous areas?

  The "-00" approval suffix stands for "No Approvals." This configuration is intended for safe-area applications. If your machine is located in a hazardous area with explosion risks, you must procure a probe with a different certification code, such as the "-05" multi-approval option.