Bently Nevada 330878-51-CN Proximity Probe High-Temperature Vibration Monitoring

In the demanding world of rotating machinery, precision monitoring is non-negotiable. The Bently Nevada 330878-51-CN is a premium 8 mm proximity probe system component, engineered by Baker Hughes to deliver uncompromising performance in high-temperature environments.

This probe is an integral part of the Bently Nevada 3300 XL line, the industry standard for eddy current technology. Designed for critical machinery protection, this sensor provides accurate, real-time data on radial vibration, axial (thrust) position, and keyphasor measurements.

Key Technical Specifications

The model 330878-51-CN follows a specific part numbering convention that defines its capabilities for industrial applications:

Type: 3300 XL 8mm Proximity Probe.

Thread Size: 3/8-24 UNF thread.

Agency Approval: Standard (General Purpose) approval.

Total Length: 5.0 meters (standard integral cable configuration).

Connector: Miniature CM (Connectorized with Armor) style.

Temperature Rating: Specifically designed for High-Temperature applications, capable of withstanding elevated thermal conditions that would degrade standard sensors.

The "High-Temperature" Advantage

The "CN" designation in this part number signifies its high-temperature capability. Standard proximity probes often fail or generate inaccurate signals when exposed to the extreme heat found near turbine bearings, steam paths, or compressors.

The 330878-51-CN is built to survive these harsh conditions. It maintains signal integrity and mechanical stability where standard probes cannot, ensuring continuous protection of your capital equipment without thermal drift.

Superior Eddy Current Technology

The Bently Nevada 3300 XL system operates using the eddy current principle. A high-frequency signal is sent from the oscillator (like the 3300 XL Proximitor) to the probe tip. As the shaft moves, the gap between the tip and the metal surface changes, modulating the signal. This results in a highly linear DC voltage output that corresponds directly to shaft position and dynamic motion.

Unlike accelerometers mounted on the bearing housing, this non-contact probe reads the actual motion of the shaft itself, providing the earliest possible warning of mechanical faults such as:

Rotor unbalance

Misalignment

Oil whirl/whip

Rubs

Applications

The 330878-51-CN is a versatile component found in a wide range of heavy industries, including:

Steam Turbines in power generation

Gas Turbines in pipeline and petrochemical facilities

Centrifugal Compressors

Hydroelectric Generators

Pumps with sleeve bearings

System Compatibility

This probe is designed to pair with the Bently Nevada 3300 XL Proximitor (e.g., 330180-50-00) and extension cables (if needed). The system's "Tip Locating" feature simplifies installation by ensuring the probe tip is correctly positioned at the center of the gap range without complex calculations, reducing installation time and error.

Why Choose the 330878-51-CN?

When a standard probe reaches its thermal limits, machinery uptime is at risk. Choosing the Bently Nevada 330878-51-CN ensures:

Reliability: Built to rigorous Bently Nevada standards, trusted by plant operators worldwide.

Accuracy: Linear measurement across the entire temperature range.

Durability: Robust construction with armor cable options to withstand vibration and abrasion.