Description

The Bently Nevada 330101-29-52-10-02-00 is an 8 mm unarmored eddy-current proximity probe belonging to the 3300 XL 8 mm Proximity Transducer System family. This non-contact sensor is designed to provide high-precision displacement, shaft position, and vibration measurements on critical rotating machinery such as steam turbines, gas turbines, centrifugal compressors, and high-speed pumps.

This specific configuration is defined by its mechanical housing and cable parameters, offering a 2.9-inch unthreaded length and a 5.2-inch overall case length with 3/8-24 UNF-2A threads. It features a 1.0-meter total cable length without mechanical armor, terminated in a miniature coaxial ClickLoc connector. This non-armored design is ideal for routing through protective conduit systems in safe-area environments where standard approvals suffice, differentiating it from variants with armored steel jackets or specialized hazard zone certificates.

The probe works on the eddy-current operating principle, generating a high-frequency electromagnetic field from its 8 mm tip. When a conductive steel target (such as a turbine shaft) moves within its linear range, the field changes are processed by a compatible 3300 XL Proximitor sensor. This change is converted into a highly stable linear voltage output proportional to the gap distance, allowing continuous monitoring of shaft dynamic vibration and static position.

Features

• Non-contact eddy-current design ensures zero mechanical wear and long-term reliability in continuous machine monitoring chains.
• Features standard 3/8-24 UNF-2A threads without protective armor, optimizing installation inside rigid or flexible external conduits.
• Equipped with a 1.0-meter high-quality standard coaxial cable terminated with a miniature coaxial ClickLoc connector.
• Offers a 2.9-inch unthreaded sleeve coupled with a 5.2-inch overall case length to match specific bearing housing insertion depths.
• Robust polyphenylene sulfide (PPS) tip and stainless steel probe body resist corrosive industrial machine environments.

Applications

• Radial vibration and shaft dynamic movement monitoring on high-speed industrial turbines.
• Axial position (thrust displacement) tracking in centrifugal compressors, gearboxes, and large water pumps.
• Bearing oil film clearance and structural motion measurement on critical rotating utility assets.
• Integration into 3500 series machinery protection systems via appropriate Proximitor sensors and I/O channels.

Ordering Information

Technical Specifications

Installation Guidelines

To ensure optimal measurement accuracy and system longevity, install the probe according to the following guidelines:

• Probe Gap Calibration: Mount the probe in the machine casing using a micrometer or a voltmeter to set the proper initial gap voltage (typically -10 Vdc, equivalent to approximately 1.27 mm or 50 mils gap space) per system calibration procedures.
• Thread Engagement: Maintain thread engagement within industry standards (maximum length of thread engagement is 0.563 inches for 3/8-24 threads). Do not over-tighten during insertion.
• Cable Protection: Route the coaxial cable through a dedicated, grounded metal conduit or tray system to prevent physical damage and isolate the transducer signals from electromagnetic interference (EMI).
• Grounding Practices: Ensure that the outer shield of the extension cable is connected to a clean instrument ground at the monitor or Proximitor panel only. Maintain insulation on the coaxial connectors inside terminal boxes.