Bentley 330100-50-03 Preamplifier (3300 XL Eddy Current Sensor System) Product Description

I. Product Overview

330100-50-03 is the preamplifier (Proximitor) of the 3300 XL series eddy current sensor system of Bently Nevada (now part of ABB), a signal processing unit for 8mm probes. Its core function is to provide high-frequency excitation signals to the probe and convert the gap changes detected by the probe into standard voltage signals, which are used for monitoring the shaft vibration, shaft displacement, phase angle, and rotational speed of rotating machinery. As a core component of the 3300 XL system, it has high precision, high stability, and strong anti-interference ability, complying with API 670 standards, and is widely used in key rotating machinery condition monitoring scenarios in power, petrochemical, metallurgy, gas turbines, etc.

II. Basic Information

Model: 330100-50-03

Brand: Bently Nevada (now part of ABB)

Series: 3300 XL 8mm Eddy Current Sensor System

Type: Preamplifier (Signal Processor)

Compatible probes: 330101/330103 series 8mm eddy current probes

Extension cable compatibility: 5-meter total length (the "50" in the model represents a 5-meter system calibration)

Installation method: standard DIN rail installation or panel installation

Protection level: IP20

Certifications: CE, UL, CSA, API 670 (Fourth Edition)

Environmental parameters: Working temperature 0°C to + 45°C, storage temperature - 51°C to + 100°C; Relative humidity 5%–95% (no condensation)

Weight: Approximately 0.5kg

Size: Standard industrial module size, compatible with control cabinet standard installation space

III. Electrical Parameters

Input Specifications

Power supply voltage: -17.5VDC to -26VDC (negative power supply)

Input signal: Receives high-frequency impedance change signals from the 8mm probe coil

Compatible probe cable: 0.5m (the model suffix "03" corresponds)

Total system cable length: 5m (probe cable + extension cable)

Output Specifications

Output sensitivity: 7.87V/mm (200mV/mil), linear error ≤ ±1%

Linear range: 2.0mm (80mil), effective measurement range 0.25mm to 2.3mm

Output signal: -1VDC to -17VDC standard DC voltage signal

Frequency response: 0–10kHz (±0/-3dB), covering the main frequency range of rotating machinery vibration

Load capacity: Can be directly connected to DCS, PLC, TSI systems or vibration monitoring instruments

IV. Core Functions

1. Signal Excitation and Processing

Built-in high-frequency oscillator, providing stable high-frequency alternating current signals to the probe coil; real-time detection of gap changes between the probe and the metal target surface, linearly converting the impedance changes caused by the eddy current effect into voltage signals, achieving non-contact precise measurement.

2. High Precision Linear Measurement

Using 3300 XL proprietary calibration technology, sensitivity stability within the full temperature range ≤ ±1.5%, linear range 2mm, compatible with shaft vibration (radial), shaft displacement (axial thrust), eccentricity, and phase angle measurement, minimum measurable displacement 0.01mm.

3. Temperature Compensation and Stability

Integrated automatic temperature compensation circuit, maintaining measurement accuracy stable within the wide temperature range of - 35°C to + 260°C for the probe and 0°C to + 45°C for the preamplifier, capable of withstanding industrial site high temperatures, low temperatures, and temperature fluctuation conditions.

4. Fault Diagnosis and Condition Monitoring

Built-in circuit self-check function can identify probe breakage, short circuit, cable faults and power supply abnormalities, and output fault status signals; it supports linkage with the Bently 3500/3300 TSI system to achieve real-time data acquisition, over-limit alarm and fault recording.

5. Interference Resistance and Compatibility

Complies with CE electromagnetic compatibility standards, tolerates EMI/RFI interference generated by frequency converters, motors, etc.; the probe, extension cable and preamplifier can be interchanged without separate matching and calibration, compatible with both new and old systems of the 3300 series, and supports on-site rapid replacement and maintenance.

V. Working Principle

Based on the eddy current effect: The preamplifier injects high-frequency alternating current into the probe coil, generating an alternating magnetic field; when the probe approaches the rotating shaft (metal conductor), the magnetic field induces eddy currents on the surface of the shaft, which act in the opposite direction on the probe coil, changing its inductance and impedance; the preamplifier detects the impedance change in real time and converts it into a voltage signal proportional to the gap; the larger the gap, the closer the output voltage is to -17V, and the smaller the gap, the closer it is to -1V, thus accurately measuring the vibration, displacement and other dynamic parameters of the shaft.

VI. Mechanical Structure and Installation

Shell: Industrial-grade flame-retardant plastic shell, sturdy and dust-proof, suitable for harsh industrial environments

Interfaces: Side equipped with probe signal interface, power supply interface and output signal interface, convenient wiring

Installation: Supports DIN rail mounting or bolt fixation, installed in a position away from strong electromagnetic interference in the control cabinet; the distance between the probe and the preamplifier needs to match a total cable length of 5 meters, and the recommended gap for probe installation is around -9VDC (midpoint of the linear range)

VII. Application Scenarios

Power industry: Axial vibration and axial displacement monitoring of steam turbines, generators, feed pumps, fans to prevent rotor friction and bearing wear and other faults

Petrochemical industry: State monitoring of centrifugal compressors, gas turbines, pump sets, mixers, to ensure continuous production

Metallurgical industry: Axial vibration and displacement monitoring of rolling mills, blast furnace fans, motors to avoid equipment overload damage

Industrial drives: Key phase, speed and eccentricity measurement of large motors, high-speed rotating equipment, providing data for dynamic balance and fault diagnosis

TSI system companion: As the core measurement unit of the 3500/3300 TSI system, constructing a protection and monitoring system for rotating machinery

VIII. Product Advantages

High reliability: Industrial-grade design, wide temperature range, tolerant of harsh working conditions such as oil mist, steam, dust, etc., with a long average downtime

High precision: 7.87V/mm standard sensitivity, small linear error, strong temperature stability, meeting API 670 high-precision requirements

Easy maintenance: Components can be interchanged, no calibration required, quick replacement after failure, reducing maintenance costs during downtime

Strong adaptability: Compatible with the entire 3300 XL series of 8mm probes, suitable for various cable lengths, compatible with new and old monitoring systems