Bently 135489-04 high-performance signal conditioning module

Bently 135489-04 is a high-performance signal conditioning module developed by Bently Nevada (now part of GE Vernova), specifically designed for the 3500 Series Rotating Machinery Monitoring System. It acts as a "signal processor" between field sensors (primarily eddy current sensors) and the 3500 system’s core monitoring modules (e.g., vibration or position monitoring modules). Its core function is to amplify, filter, and linearize weak raw signals from sensors, ensuring high-precision, low-noise data transmission to the system—critical for accurate monitoring of rotating machinery (such as turbines, generators, and compressors) and early fault diagnosis. Below is its detailed information:

I. Core Technical Parameters

Category	Specific Specifications
Applicable System	Exclusive to Bently Nevada 3500 Series Monitoring System (compatible with 3500/10, 3500/20 frames and 3500/42 vibration modules)
Target Sensors	Dedicated to Bently 3300/3500 Series eddy current displacement sensors (e.g., 3300 XL 8mm, 3500 5mm probes)
Signal Input	- Input type: Differential eddy current sensor signals (microvolt-level, 0-5V peak-to-peak)- Input impedance: ≥10MΩ (to avoid loading sensor output)
Signal Output	- Output type: Linearized analog voltage signals (0-10V DC, proportional to sensor-measured displacement)- Output impedance: ≤100Ω (compatible with 3500 monitoring module inputs)- Linearization accuracy: ±0.1% FS (full scale)
Electrical Performance	- Gain range: 100-1000x (adjustable via internal trim potentiometer)- Bandwidth: 0-10kHz (covers typical rotating machinery vibration frequency ranges)- Noise level: ≤50μV rms (at 1kHz bandwidth, ensuring signal purity)

1. High-Precision Signal Conditioning

Eddy current sensors output weak, non-linear raw signals (microvolt-level) that are easily distorted by field interference. The 135489-04 module solves this by:

Amplification: Adjustable gain (100-1000x) boosts weak sensor signals to a standard 0-10V DC range, matching the input requirements of 3500 monitoring modules and improving signal-to-noise ratio (SNR) by ≥30dB.
Linearization: Built-in digital linearization algorithms correct the inherent non-linearity of eddy current sensors (typically ±2% error), reducing measurement error to ±0.1% FS—critical for accurate shaft vibration (e.g., ≤0.1μm resolution) and axial position monitoring.
Filtering: Integrated low-pass filters (cutoff frequency adjustable up to 10kHz) suppress high-frequency electromagnetic interference (EMI) from nearby motors or high-voltage cables, ensuring only valid vibration/position signals are transmitted.