Bently Nevada 330104-18-22-10-02-00 Proximity Transducer – 3300 XL Series

Bently Nevada 330104-18-22-10-02-00: Eddy Current Proximity Transducer in Rotating Machinery Protection Loops

The 330104-18-22-10-02-00 is a complete three-component eddy current proximity transducer assembly manufactured by Bently Nevada, operating within the 3300 XL platform. Its primary function is continuous, non-contact measurement of radial shaft displacement and vibration in rotating machinery — turbines, compressors, pumps, and gearboxes — where contact-based sensing is mechanically impractical and signal latency is operationally unacceptable.

This assembly is configured as follows: 18 mm probe diameter, 22-inch (558.8 mm) integral armored cable, 10-meter coaxial extension cable, standard 200 mV/mil (7.87 V/mm) sensitivity, and a nominal –24 VDC bias output. The configuration code 02-00 designates standard connector termination and non-intrinsically-safe driver pairing, making it the default selection for general-purpose industrial installations not requiring ATEX Zone 0 compliance.

In a machinery protection control loop, this transducer occupies the front-end sensing position. Its analog DC output feeds directly into Bently Nevada 3300 series monitor cards — such as the 3300/16 Dual Vibration Monitor or the 3300/25 Keyphasor Module — where the signal is conditioned, compared against alarm and danger setpoints, and used to drive relay outputs for automatic machine shutdown. The transducer’s DC-to-10,000 Hz frequency response ensures that both quasi-static shaft position drift (thermal bow, bearing wear) and high-frequency vibration events (blade passing frequency, subsynchronous instability) are captured within a single measurement channel without signal aliasing.

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

Technical Parameters

Hardware Logical Analysis

The 330104-18-22-10-02-00 operates on the principle of electromagnetic impedance modulation. The probe tip houses a flat coil wound on a ferrite core, driven by the oscillator stage of the paired driver/oscillator-demodulator at a carrier frequency of approximately 1.0 MHz. When the probe tip is positioned within its linear range of a conductive target, eddy currents are induced on the target surface. These eddy currents create a counter-magnetic field that loads the probe coil, reducing its effective inductance and increasing resistive losses — a measurable change in coil impedance proportional to the air gap distance.

The driver’s demodulator stage extracts this impedance variation from the carrier signal and converts it to a DC voltage output. The transfer function is linear within the 25–325 mil gap range, with a slope of exactly 200 mV/mil. The –24 VDC bias at mid-gap (approximately 175 mil) allows the monitor card to detect both positive and negative gap excursions — shaft moving toward or away from the probe — without signal clipping.

EMC Design: The coaxial extension cable uses a double-shielded construction with a low-capacitance dielectric. The outer shield is grounded at the driver end only (single-point grounding), preventing ground loop currents from injecting common-mode noise into the signal path. This architecture maintains signal integrity in environments with high-frequency switching noise from variable-frequency drives (VFDs) operating at 2–16 kHz carrier frequencies — a common interference source in compressor and pump stations.

Thermal Stability: The probe coil assembly uses a temperature-compensated ferrite core material. Over the –35°C to +121°C probe operating range, sensitivity drift is maintained within ±1% of nominal — a critical specification for steam turbine applications where probe body temperatures can approach 100°C during normal operation. The integral cable’s armored jacket provides mechanical protection against abrasion and vibration fatigue at the probe-to-cable junction, which is the highest-stress point in the assembly.

Calibration Traceability: Each 330104 assembly is factory-calibrated as a matched system — probe, integral cable, and extension cable are characterized together. The calibration data is encoded in the driver’s trim resistor network. Substituting any individual component without recalibration introduces a systematic sensitivity error that cannot be corrected at the monitor card level, which is why field cable length modification is not supported.

System Integration Benefits

• Direct 3300 Monitor Compatibility: The –24 VDC bias output and 200 mV/mil sensitivity are the native input specification for all 3300 XL series monitor cards. No signal conditioning, impedance matching, or scaling is required at the monitor input — the transducer output connects directly to the monitor’s BNC or terminal block input, eliminating potential signal chain errors introduced by intermediate conditioning hardware.
• Deterministic Real-Time Response: The DC-coupled output path from probe to monitor card introduces zero group delay across the measurement bandwidth. Vibration events at frequencies up to 10 kHz are represented in the monitor’s output within one carrier cycle (approximately 1 µs), ensuring that the protection system’s alarm and trip relay response time is governed solely by the monitor card’s processing latency — typically 20–100 ms for 3300 series cards — not by transducer bandwidth limitations.
• Dual-Parameter Measurement from a Single Channel: The DC component of the output represents average shaft centerline position (useful for bearing wear trending and thermal bow detection), while the AC component represents dynamic vibration amplitude. Both parameters are extracted simultaneously by the 3300 monitor card without requiring separate measurement channels, reducing rack slot consumption and wiring complexity.
• API 670 Alarm Setpoint Integrity: Because the transducer’s sensitivity is factory-certified to ±10% of 200 mV/mil, alarm and danger setpoints entered in engineering units (mil or µm) at the monitor card are directly traceable to physical shaft displacement without field calibration verification. This satisfies API 670 Section 5.3 requirements for setpoint traceability in machinery protection systems.
• Non-Intrusive Installation: The 18 mm probe diameter fits standard API 670-compliant probe boss dimensions machined into bearing housings. No shaft modification, keyway, or target preparation is required for standard AISI 4140 steel shafts. Installation is limited to probe mounting, gap setting to 175 mil (mid-range), and cable routing — a procedure completable during a planned outage window of less than two hours per measurement plane.
• Diagnostic Transparency via Bias Voltage Monitoring: The –24 VDC bias output serves a secondary diagnostic function: a bias voltage outside the –18 to –26 VDC window indicates a probe gap error, a cable open circuit, or driver power supply failure. This self-diagnostic signal is monitored continuously by the 3300 series monitor card and generates a Not OK relay output, providing immediate fault annunciation without requiring manual inspection of the transducer installation.
• Scalable Redundancy Architecture: Multiple 330104-18-22-10-02-00 assemblies can be installed at 90° or 120° angular offsets around the same bearing plane to implement redundant vibration measurement per API 670 Section 6. The monitor card’s voting logic (2-out-of-3 or 1-out-of-2) uses the individual transducer outputs independently, so a single transducer failure does not cause a spurious machine trip — it generates a maintenance alert while the remaining channels continue protection coverage.
• Long-Term MRO Availability: The 330104 series has been in continuous production since the early 3300 platform generation. The 18 mm probe diameter and 10-meter extension cable configuration is the highest-volume variant, ensuring consistent availability through authorized distribution and MRO channels. Replacement units are drop-in compatible with existing monitor rack configurations without firmware updates or monitor card reconfiguration.

Quality Assurance & Global Logistics

Every 330104-18-22-10-02-00 unit supplied through siemensplc.com is sourced as genuine Bently Nevada original equipment — not aftermarket, not cloned, and not rebranded. Units are procured through authorized industrial distribution channels and verified OEM surplus programs. Prior to dispatch, each assembly undergoes a structured pre-shipment inspection protocol: visual examination of probe tip, coil housing, and connector terminations; continuity and insulation resistance check on the extension cable; and documentation verification confirming part number, date code, and configuration code against the physical label.

Shipments originate from our warehouse in Xiamen, China — a major international logistics hub with direct access to DHL Express, FedEx International Priority, and UPS Worldwide Expedited services. Standard transit times are 3–5 business days to Europe and North America, 2–3 business days to Southeast Asia and the Middle East. All shipments are packed to IEC 60068-2 transport vibration and shock standards: probe assemblies are individually foam-cushioned, extension cables are coiled to a minimum bend radius of 10× cable diameter, and the complete assembly is sealed in an anti-static bag before boxing. Export documentation — commercial invoice, packing list, and HS code 9031.80 classification — is prepared for customs clearance in all major import jurisdictions.

A 12-month warranty against manufacturing defects is provided on all units. Warranty claims are processed within 5 business days of receipt of the returned unit. Technical support — including gap setting guidance, cable routing recommendations, and monitor card compatibility verification — is available directly from our engineering team via email and WhatsApp at no additional charge.

Contact Information

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