Bently Nevada 330878-91-05 3300 XL 50 mm Proximitor Sensor

Description

Option 91 (9.0 meters system length, DIN mount) and Option 05 (Multiple Approvals) specify this 3300 XL 50 mm Proximitor Sensor configuration — 330878-91-05. This unit works with a 3300 XL 50 mm proximity probe and extension cable as part of a complete non-contact eddy-current displacement measurement system. It is used for shaft vibration and axial position measurement on large turbine rotors and machinery with oversized targets where displacement ranges exceed standard limits.

Unlike variants configured for panel mounting (such as Option 90) or shorter 5.0-meter system lengths (such as Option 51), this specific configuration is tailored for DIN rail installation with a total system length of 9.0 meters. The integrated SpringLoc terminal strips facilitate fast field wiring connections without requiring specialized tools. Improved radio frequency interference (RFI) and electromagnetic interference (EMI) immunity allow this sensor to meet CE marking standards without specialized shield housing.

Features

• Option 91 specifies a 9.0-meter system calibration designed for DIN rail mounting configurations.
• Option 05 provides multiple agency approvals including ATEX, IECEx, and CSA hazardous area certifications.
• Extended linear range of 27.9 mm (1100 mils) starting at 1.3 mm (50 mils) from the target.
• Average Scale Factor (ASF) of 394 mV/mm (10 mV/mil) nominal for high-displacement environments.
• SpringLoc terminal strips simplify connection procedures and resist loosening under vibration.
• Built-in test points allow signal verification using standard instruments without interrupting field wiring.
• Backward compatibility with standard 3300 XL 50 mm proximity probes and extension cables.

Applications

• Steam turbine generator set differential expansion (DE) monitoring
• Large industrial gas turbine rotor position measurements
• Axial displacement monitoring on oversized shaft assemblies
• High-displacement target tracking in power generation and petrochemical facilities
• Industrial machinery with heavy vibration and environmental exposure

Ordering Information

Technical Specifications

Connections and Interfaces

Installation Guidelines

• DIN rail mounting utilizes the integrated DIN pad designed for a standard 35 mm DIN rail. Allow an additional 3.05 mm of clearance to remove the module from the rail.
• Ground the shield of the extension cable at the Proximitor Sensor housing. Do not ground the coaxial shield at any other point to prevent ground loops.
• Use recommended three-conductor shielded triad field cable (18 AWG or similar) for runs from the Proximitor Sensor to the monitor rack.
• Maintain minimum target size requirements of 102 mm (4.0 inches) flat target diameter when verifying system calibration.
• Calibrate the probe gap using the physical movement of a sliding bracket or spindle micrometer prior to locking the case threads.

Compliance and Certifications

• ATEX/IECEx: Ex ia IIC T4/T5 Ga, Ex ia IIIC T90C/T105C Dc, Ex nA IIC T4/T5 Gc, Ex ec IIC T4/T5 Gc (Option 05)
• CSA/CNRTLus: Class I, Zone 0: AEx/Ex ia IIC T4/T5 Ga; Class I, Groups A, B, C, D; Class II, Groups E, F, G; Class III
• European CE Mark: Compliant with EMC Directive 2014/30/EU and RoHS Directive 2011/65/EU
• Electromagnetic Compatibility Standards: EN 61000-6-2, EN 61000-6-4
• China RoHS: 15-year Environment Friendly Use Period (EFUP)