Product Overview

The Bently Nevada 330878-90-05 is a specialized eddy current signal conditioner designed for the 3300 XL 50mm Transducer System. This Proximitor Sensor is engineered to provide the industry’s most extensive linear measurement range, specifically for monitoring Differential Expansion (DE) in large-scale steam turbine generators. It processes the raw signal from a 50mm proximity probe and converts it into a usable voltage output proportional to the distance between the probe tip and the target.

By facilitating precise measurements of the relative thermal growth between the turbine rotor and the stator, the 330878-90-05 plays a vital role in preventing axial interference and potential machinery failure during startup and operational transients. This model is intended for panel-mount configurations and offers seamless integration with standard monitoring racks and Turbine Supervisory Instrumentation (TSI) systems.

Technical Specifications

• Manufacturer: Bently Nevada (Baker Hughes)

• Model Number: 330878-90-05

• System Series: 3300 XL 50 mm

• Linear Range: 27.9 mm (1100 mils)

• Extended Measurement Capability: Up to 56 mm (2.2 inches) in complementary configurations

• Input Voltage: -24 Vdc

• Output Signal: 0.394 V/mm (10.01 mV/mil)

• Mounting: 4-hole panel mount or DIN-rail (with adapter)

• Connector Type: Gold-plated coaxial ClickLoc

• Enclosure Rating: IP20

• Operating Temperature: -35°C to +85°C (-31°F to +185°F)

• Dimentions:3.5x2.6x10 cm

Core Functional Characteristics

• Extended Displacement Sensing: Provides the longest linear range in the Bently Nevada eddy current portfolio, allowing for the monitoring of large axial movements in high-capacity turbines.

• Dual-Transducer Versatility: Supports both single-probe installations for standard ranges and dual-probe "complementary" setups for applications requiring measurement of extreme rotor growth up to 56 mm.

• Precision Signal Conversion: Utilizes advanced internal electronics to maintain a stable scale factor even in the presence of temperature fluctuations and electromagnetic interference.

• System Interchangeability: Part of the fully compatible 3300 XL line, allowing the sensor to be used with standard 50mm probes and extension cables without requiring custom factory calibration.

• Rugged Construction: Housed in a durable casing designed for long-term installation in industrial control cabinets, ensuring protection against typical power plant environmental stressors.

Primary Applications

The 330878-90-05 is a critical asset for power generation facilities, specifically used to monitor:

• Differential Expansion in high-pressure (HP) and intermediate-pressure (IP) steam turbines.

• Relative thermal growth between turbine casings and rotors.

• Ramp and collar position monitoring near thrust bearings.

• Large-scale axial displacement in heavy industrial rotating machinery.