Bently Nevada 330101-00-31-20-02-00 Proximity Probe – 3300 XL Series

Bently Nevada 330101-00-31-20-02-00 — Eddy-Current Proximity Probe for Rotating Machinery Protection

The Bently Nevada 330101-00-31-20-02-00 is a 5 mm tip-diameter, eddy-current proximity probe belonging to the 3300 XL Proximity Transducer System. It operates on the principle of electromagnetic induction: a high-frequency oscillator (typically 1.0 MHz) drives a coil embedded in the probe tip, generating an alternating magnetic field. When a conductive target — typically AISI 4140 steel shaft — enters this field, eddy currents are induced on the target surface, loading the oscillator circuit and producing a proportional DC voltage output. This non-contact, wear-free measurement principle makes the 330101-00-31-20-02-00 the standard transducer of choice for continuous shaft vibration and axial position monitoring in API 670-compliant machinery protection systems.

The probe is rated for a linear measurement range of 0 to 2 mm (80 mil), with a nominal sensitivity of 7.87 V/mm (200 mV/mil) when paired with a compatible Bently Nevada Proximitor® sensor such as the 330180 or 330181 series. The output is a negative DC voltage referenced to common, allowing direct interface with 3300 XL monitor cards without signal conditioning intermediaries. The 200 mm integral cable terminates in a 3-pin MIL-C-5015 style connector, providing mechanical robustness in high-vibration environments.

Operating temperature range spans −35 °C to +177 °C, enabling deployment in both ambient-temperature compressor trains and high-temperature steam turbine bearing housings. The probe body is constructed from 316 stainless steel with a PEEK (polyether ether ketone) tip insert, offering resistance to hydrocarbon condensates, lubricating oils, and mild acidic atmospheres encountered in petrochemical and power generation facilities.

Real-time Stock & RFQ: [email protected] | WhatsApp: +86 18359268345

Technical Parameters

Hardware Logical Analysis

The 330101-00-31-20-02-00 implements a passive probe / active Proximitor® architecture, separating the oscillator-demodulator electronics from the probe body. This design decision has two direct engineering consequences: first, the probe tip itself contains no active components, eliminating failure modes associated with thermal cycling of semiconductor junctions in high-temperature bearing housings; second, the Proximitor® sensor can be mounted in a cooler, accessible location, simplifying maintenance without disturbing the probe installation.

EMC Design: The coaxial construction of the integral cable — with the center conductor carrying the oscillator drive signal and the outer shield referenced to the Proximitor® common — provides inherent rejection of common-mode electromagnetic interference. In environments with variable-frequency drives (VFDs) and high-current bus bars, this shielded topology attenuates capacitively coupled noise by typically 40–60 dB across the 50 Hz–100 kHz band, preserving measurement integrity at the sub-micron displacement level.

Thermal Stability: The PEEK tip insert exhibits a coefficient of thermal expansion (CTE) of approximately 50 µm/m·°C, closely matched to the 316 stainless steel housing (CTE ~16 µm/m·°C). While not identical, the mechanical interface is designed with a controlled interference fit that maintains coil geometry stability across the rated temperature range, limiting sensitivity drift to within ±0.5% of nominal across the full −35 °C to +177 °C span.

Target Interaction Geometry: The 5 mm tip diameter defines the effective sensing zone diameter at approximately 2× the tip diameter (10 mm). For accurate radial vibration measurement, the shaft diameter must be at least 5× the probe tip diameter (≥25 mm), and the target surface must be free of scratches, plating discontinuities, or residual magnetism exceeding 2 Gauss — all per API 670 Annex D requirements. Non-compliance with target surface specifications is the most common source of measurement error in field installations.

Redundancy Compatibility: The 330101-00-31-20-02-00 is fully compatible with dual-probe redundant configurations used in API 670 radial vibration channels. In such arrangements, two probes are mounted 90° apart (X–Y configuration) on the same bearing plane, enabling orbit plot generation and directional vibration analysis. The 3300 XL monitor cards support automatic channel voting logic, maintaining protection integrity if one probe channel fails.

System Integration Benefits

• Zero mechanical wear: Non-contact eddy-current principle eliminates probe-to-shaft contact, supporting continuous 24/7 monitoring without scheduled probe replacement intervals.
• Direct 3300 XL monitor compatibility: Output signal levels and impedance characteristics are factory-matched to 3300 XL monitor input cards, requiring no signal conditioning adapters or impedance matching networks.
• Deterministic response time: The analog DC output tracks shaft displacement with a bandwidth of DC to 10 kHz (−3 dB), capturing sub-synchronous, synchronous, and super-synchronous vibration components within a single measurement channel.
• API 670 alarm setpoint traceability: Calibrated sensitivity of 7.87 V/mm allows direct engineering-unit scaling in the monitor, enabling alarm and danger setpoints to be entered in µm or mil without conversion factors.
• Hazardous area deployment: Compatible with Bently Nevada 3300 XL Zener Barrier assemblies for ATEX/IECEx Zone 1 installations, extending applicability to gas compression and offshore platform environments.
• Diagnostic transparency: The Proximitor® output voltage at the gap center (nominally −10 VDC at 1.0 mm gap) provides a static DC level that maintenance technicians can measure with a standard voltmeter to verify probe gap without removing the probe from service.
• Orbit and centerline analysis: In X–Y dual-probe configurations, the two orthogonal DC outputs feed directly into DCS or condition monitoring software for real-time shaft orbit display, centerline position trending, and bearing wear prognosis.
• Interchangeable within 3300 XL ecosystem: The 330101-00-31-20-02-00 is a drop-in replacement for earlier 3300 series probes of equivalent tip diameter and cable length, preserving existing Proximitor® and monitor card investments during plant upgrades.

Quality Assurance & Global Logistics

Every Bently Nevada 330101-00-31-20-02-00 unit dispatched from our Xiamen, China facility is sourced through authenticated supply channels with full traceability to Baker Hughes / Bently Nevada authorized distribution networks. Prior to shipment, each probe undergoes a structured inspection protocol: housing and connector integrity check against OEM dimensional references, cable sheath continuity verification, label and date-code authentication, and static gap voltage verification using calibrated Proximitor® bench equipment.

Shipments originate from Xiamen, China with the following logistics options:

• Express Air (DHL / FedEx / UPS): 3–7 business days to North America, Europe, Southeast Asia, and the Middle East.
• Economy Air: 7–14 business days for cost-sensitive procurement.
• Sea Freight: Available for bulk orders of 10+ units; lead time quoted per destination port.

All export shipments include a commercial invoice, packing list, certificate of origin, and customs declaration. Anti-static foam inserts and moisture-barrier packaging protect probe tip geometry and connector contacts during transit. A 12-month warranty covers manufacturing defects from the date of shipment. Warranty claims are processed within 5 business days of receipt of the returned unit.

Contact Information

Email: [email protected]
WhatsApp: +86 18359268345
Web: siemensplc.com
Location: Xiamen, China
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