7200 Series 8mm Eddy Current Proximity Sensor 21508-02-12-10-02 by Bently Nevada

Product Overview

The Bently Nevada 7200-21508-02-12-10-02 is a high-accuracy, 8mm reverse-mount proximity probe engineered to continuously monitor the structural health of critical industrial machinery. By utilizing advanced eddy current technology, this heavy-duty sensor translates physical gap adjustments between the probe tip and a moving shaft into a linear, dynamic analog voltage signal.

Application and Operation

Control systems rely heavily on this data to capture axial thrust position, radial shaft vibration, and rotational speed without creating mechanical wear. Because heavy industrial machinery operates under intense thermal and kinetic stress, plant operators implement this probe across diverse, high-stakes rotating assets to preserve equipment runtime, such as:

• High-pressure industrial compressors and multi-stage process pumps
• Steam, gas, and hydro utility turbines
• Large-scale electric motors and power generators
• Industrial centrifuges and high-speed reciprocating machinery

Technical Characteristics and Breakdown

The specialized reverse-mount engineering allows maintenance specialists to install the hardware safely from outside the machine casing into tight internal spaces or custom sleeve assemblies. Furthermore, the ruggedized body construction completely isolates the sensitive internal coil from extreme temperature fluctuations and aggressive chemicals like lubricants, water, or sulfuric acid. Consequently, the sensor interfaces seamlessly with industry-standard 3300, 3500, or 9000 monitor racks to maintain continuous, API 670 compliant machinery diagnostics.

The detailed nomenclature code 7200-21508-02-12-10-02 dictates specific performance values and physical dimensions tailored for specialized plant installations:

• Linear Measurement Range: Captures a broad 80-mil (2.0 mm) span, giving tracking systems ample scale to monitor standard deviations and severe mechanical runout.
• Scale Factor Sensitivity: Operates at a precise 200 mV/mil (7.87 V/mm) output ratio, which ensures reliable, high-resolution data transmission across long field cable runs.
• Frequency Response Range: Tracks rapid mechanical changes across an expansive spectrum from 0 Hz (pure static DC) up to a fast 10 kHz dynamic ceiling.
• Unthreaded Body Length: Utilizes a highly compact 0.2-inch unthreaded shoulder configuration to assist with flush installation brackets.
• Overall Case Length: Features a extended 12.0-inch total case depth, which allows the probe to penetrate deep through dense casing walls.
• Total Integrated Cable Length: Employs a 1.0-meter (approximately 39 inches) integrated coaxial lead to connect with proximity extension cables.

Specifications Table