330851-02-000-050-10-00-CN Bently Nevada 25mm Proximity Probe

Product Overview

The Bently Nevada 330851-02-000-050-10-00-CN is a high-performance 3300 XL 25 mm proximity probe engineered for superior vibration and position monitoring in critical machinery. Specifically optimized for the demanding environments of large steam turbine driven equipment, this non-contact eddy current sensor replaces legacy 7200-series 25mm and 35mm systems. 

Technical Configuration & Suffix Logic

The model code for the 330851-02-000-050-10-00-CN defines its precise mechanical and electrical interface to ensure a perfect fit for turbine monitoring applications.

Mechanical Interface Configuration

• 02 (Probe Case Type): Features an M30x2 metric thread for standard industrial mounting.
• 000 (Unthreaded Length): 0 mm unthreaded portion; the case is fully threaded for maximum adjustment flexibility.
• 050 (Overall Case Length): A total case length of 50 mm, providing a compact profile for confined installation spaces.

Electrical & Environmental Options

• 10 (Total Length): 1.0 meter (3.3 feet) total probe length, optimized for high-frequency response and signal integrity.
• 00 (Armor): Standard PFA insulated FluidLoc cable without stainless steel armor, keeping the unit weight at a precise 230g.
• CN (Agency Approval): Specifically certified for regional regulatory compliance and intrinsic safety requirements.

Technical Specifications

Engineering Installation & Gap Guide

Precision installation of the 330851-02-000-050-10-00-CN is vital for valid TSI (Turbine Supervisory Instrumentation) data.

Torque & Mounting

When installing the M30x2 threaded case, the recommended mounting torque is 68 N·m (50 ft·lb). Do not exceed the maximum rated torque of 163 N·m (120 ft·lb), as over-tightening can distort the case and damage the internal eddy current coils. The compact 230g mass of the probe ensures minimal mechanical resonance during high-vibration operation.

Intrinsic Safety Compliance

For hazardous area deployments, this probe must be installed with certified Zener barriers (per drawing 141092) or galvanic isolators. The 330851-02-000-050-10-00-CN is rated for Class I, Zone 0 and Zone 2 environments when used with approved Bently Nevada Proximitor sensors.

Engineering Advantages

• Steam Environment Survivability: The FluidLoc cable prevents moisture and oil from wicking through the cable into the connector, ensuring long-term signal stability.
• Optimal Mass-to-Strength Ratio: At just 230g, the probe provides extreme durability without adding significant load to the mounting brackets.
• Non-Contact Precision: Ideal for measuring differential expansion and axial thrust where physical contact with the shaft is impossible.
• Interchangeability: Designed to physically replace legacy 7200-series 25mm systems without extensive mechanical modification.

Technical FAQs

Q1: What is the benefit of the PEEK tip material on the 330851-02-000-050-10-00-CN?
A1: PEEK provides exceptional chemical resistance and structural integrity at extreme temperatures, preventing tip deformation in high-pressure steam environments.

Q2: Why is the weight of the 330851-02-000-050-10-00-CN specified at 230g?
A2: 230g is the nominal weight for the minimum length case with a 1m lead and no armor. If armor were added, the weight would increase to approximately 330g.

Q3: Can I use this probe with a standard 3300 XL 8mm Proximitor?
A3: No. 25 mm probes require a specific 3300 XL 25 mm Proximitor Sensor to properly calibrate the larger linear range and eddy current field.