Product Overview

The Bently Nevada 330104-00-22-10-02-CN is an industrial-grade 3300 XL 8 mm Proximity Probe designed for critical machinery protection systems (MPS) and continuous turbomachinery condition monitoring. Operating via the non-contacting eddy current principle, this transducer provides high-accuracy dynamic displacement data to monitor radial shaft vibration, axial thrust position, and speed/phase reference (Keyphasor) telemetry on high-speed rotating assets.

The 3300 XL 8 mm sensor platform delivers a reliable linear operating range of 2.0 mm (80 mils). It maintains an exceptionally flat thermal response across wide internal machinery temperature fluctuations, ensuring excellent repeatability where minor calibration drift could cause a false trip on a multi-megawatt asset. By eliminating thermal instability, the probe ensures dependable machine protection under continuous load.

This specific physical configuration utilizes an English fractional 3/8-24 UNF threaded body, a 0.0-inch unthreaded length (fully threaded), a 2.2-inch overall case length, a 1.0-meter (3.3 feet) integrated unarmored coaxial cable, and a gold-plated miniature coaxial ClickLoc connector. Certified with the CN Ex-agency Approval package, this probe is strictly compliant with NEPSI / CCC intrinsic safety (IS) and non-incendive engineering standards, making it the preferred choice for hazardous processing facilities across China and region-specific regulated industries.

Technical Specifications

Model Configuration Explanation

The model identifier 330104-00-22-10-02-CN dictates specific mechanical dimensions and legal zoning certifications according to the Bently Nevada ordering matrix:

• 330104: Base model designation for the standard 3300 XL 8 mm Proximity Probe with an English fractional thread body (3/8-24 UNF).
• 00: Unthreaded Length Option. Specifies 0.0 inches. The probe body is fully threaded down to the tip transition, allowing full insertion depth adjustments inside mounting brackets.
• 22: Overall Case Length Option. Designates a 2.2-inch total case length, providing a compact structural body to pass through standard machine casings or bearing house portals.
• 10: Total Length Option. Dictates a 1.0-meter (3.3 feet) integrated cable lead, which safely extends the connection point outside the main fluid-swept area.
• 02: Connector and Cable Type Option. Selects a standard unarmored flexible coaxial cable terminated with a miniature coaxial ClickLoc connector. This configuration provides a tight bend radius for easier routing within internal bearing pathways.
• CN: Agency Approval Option. NEPSI / CCC certification package. This verifies intrinsic safety compliance under National Supervision and Inspection Centre for Explosion Protection and Safety of Instrumentation guidelines.

Typical Applications

The 330104-00-22-10-02-CN proximity probe is essential for monitoring machine health across high-reliability process sectors, especially where unarmored cables are routed inside protective conduit sleeves or dedicated wire channels:

• Radial Shaft Vibration: Positioned in dual X-Y orthogonal layouts on fluid-film (journal) bearings to trace orbital paths, cross-axis dynamics, and oil whirl/whip anomalies.
• Axial Thrust Position: Installed in dual-redundant or triple-modular redundant (TMR) configurations targeting shaft thrust collars to track axial drift and prevent internal rotor-to-stator contact.
• Keyphasor Phase Reference: Monitors single notches or keyways on rotating shafts to establish precise once-per-revolution phase timing for machine balancing and diagnostic tracking.
• Machinery Categories Covered: Centrifugal gas compressors, heavy steam turbines, process air fans, industrial turbo-expanders, and high-pressure boiler feed pumps.

System Compatibility

To maintain compliance with API 670 operational criteria, the 330104 proximity probe must be combined with its matching 3300 XL system elements:

• Extension Cable Selection: Must pair with a 3300 XL 8 mm Extension Cable (such as the 330130 series). Because the integrated probe cable length is 1.0 meter, it must be paired with either a 4.0-meter or 8.0-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 supplies the radio frequency (RF) excitation to the probe tip and translates the return eddy current impedance changes into a linear -24 Vdc voltage representation.
• Protection Monitors: Links via terminal blocks directly to the backplane inputs of the Bently Nevada 3500/42M Proximitor Seismic Monitor module, the 3500/25 Keyphasor card, or distributed Orbit60 machine protection architectures.

Hardware Integration & Gapping Guidelines

• Target Surface Requirements: Verify that the shaft observation path is free of deep grinding marks, score lines, or metallurgic variations. A surface finish of 0.8 micrometers (32 microinches) Ra or better is required to eliminate electrical runout.
• Setting the Operating Gap: Thread the probe into its mounting bracket while monitoring the DC bias voltage at the Proximitor Sensor output terminals. Turn the body until the meter shows -10.0 Vdc, marking the precise midpoint of the 2.0 mm linear tracking envelope.
• Radial Clearance Envelope: Provide a minimum counterbore diameter of 30 mm (1.2 inches) surrounding the 8 mm tip to prevent side-view interference from the mounting bracket structure.
• Preventing Sensor Cross-Talk: 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 Stability: Minimal scale factor drift over its full temperature range ensures accurate displacement metrics during cold machine starts and peak thermal cycles.
• Tool-Less ClickLoc Connectors: Gold-plated brass coaxial connectors engage with a positive click, resisting corrosion and vibration disconnects without 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.
• High 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.
• Component Interchangeability: Precision-controlled characteristic capacitance and impedance enable direct drop-in replacement without re-tuning the monitoring rack.

Ordering Information

Procurement Note: For new installation drop-ins, verify your required total loop length (5.0m or 9.0m) to ensure the matching 3300 XL Extension Cable and Proximitor Sensor are requested concurrently with this probe.

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 330104-00-22-10-02-CN probe with a standard 5.0-meter extension cable?

  No, it requires a 4.0-meter extension cable. The integrated 1.0m cable must combine with a 4.0m cable to maintain the required 5.0m total system electrical loop tuning.

• What does the "CN" suffix indicate at the end of the part number?

  The "CN" designation signifies NEPSI and CCC explosion-proof certifications, required for intrinsically safe industrial applications within China.

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

  The nominal scale factor is 7.87 V/mm (200 mV/mil) when paired with a matching 3300 XL extension cable and Proximitor sensor.

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

  The unarmored cable provides a tighter bend radius and smaller outer profile, making it ideal for routing through existing rigid or flexible field conduits.

• What is the minimum bend radius for this unarmored coaxial cable?

  Maintain a minimum bend radius of 25.4 mm (1.0 inch). Kinking the cable past this limit permanently degrades structural impedance, causing severe calibration tracking errors.

• Does this proximity probe require routine calibration fields adjustments?

  No. The 3300 XL series features complete factory interchangeability. As long as the total system loop length is maintained, you can swap components without field tuning.

• What target material is this proximity probe calibrated against?

  It is factory-calibrated against AISI 4140 electric steel. Target metals with higher chromium or aluminum content will alter the sensor's scale factor accuracy.

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

  Measure the DC voltage across the Proximitor Sensor's output terminals. A reading near 0 Vdc points to a shorted line, while -24 Vdc indicates an open loop or a cut cable.