Bentley 3300/80 Dual-Channel Vibration Monitoring Module - Detailed Product Description

I. Product Overview

The Bentley 3300/80 is the core dual-channel vibration monitoring module of the 3300 series TSI (Turbo Generator Instrumentation) system under Baker Hughes. It is specifically designed for radial shaft vibration monitoring of industrial large-scale rotating machinery. It adopts a standard 19-inch rack-mounted modular structure and supports hot-swappable operation, enabling disassembly, replacement, and installation without power interruption. This module is used in combination with the 3300 XL series 5mm or 8mm eddy current sensing systems, integrating signal acquisition, fault self-diagnosis, multi-level alarms, relay interlock outputs, and basic configuration functions. It strictly adheres to the API 670 industry standard and features high precision, high stability, and strong anti-interference capabilities. The product is widely used in non-explosive areas of industries such as power, petrochemicals, metallurgy, and cement, and is suitable for key equipment such as steam turbines, gas turbines, centrifugal compressors, generator sets, large pump sets, and fans, enabling online vibration monitoring, fault early warning, and safety shutdown protection, ensuring stable equipment operation and reducing unplanned downtime risks.

II. Model Coding Rules

3300: This is the classic 3300 series modular TSI system of Bentley, installed in a standard 19-inch cabinet rack, supporting multi-module combination expansion, centralized power supply, and hot-swappable replacement.

80: Function code, defined as a dual-channel pure vibration monitoring module, equipped with two completely independent signal input channels, specifically for radial shaft vibration measurement, and is the core model of the 3300 series vibration monitoring.

Subsequent coding (configuration bits):

Bit 1 (Input Specification): 01 = Compatible with 3300 XL 5mm eddy current probe; 02 = Compatible with 3300 XL 8mm eddy current probe.

Bit 2 (Range and Sensitivity): 00 = Standard range 0-2mm peak-to-peak, sensitivity 7.87V/mm; 01 = Custom range or sensitivity.

Bit 3 (Frequency Response): 00 = Standard frequency response 1-800Hz; 01 = Low-frequency extension; 02 = High-frequency extension.

Bit 4 (Output Function): 00 = No analog output, only relay alarm; 01 = With 4-20mA analog output; 02 = With 0-10V analog output.

III. Core Functions

Dual-channel Independent Vibration Monitoring: The two input channels' circuits are completely isolated, without signal crosstalk, capable of simultaneously conducting continuous real-time vibration measurement for two different radial measurement points of the equipment. A single module can achieve dual-point monitoring, effectively saving rack installation space, and meeting the requirements of dual-bearing or multi-measurement point equipment monitoring.

All-round Fault Self-Diagnosis: Built-in OK fault self-check circuit, 24-hour real-time monitoring of the working status of the probe, extension cable, and preamplifier. It can accurately identify sensor circuit breakage, short circuit, signal over-limit, abnormal probe gap, etc., clearly distinguishing between the actual mechanical faults of the equipment and sensor component faults, significantly reducing the probability of on-site false alarms and false interlocks.

Multi-level Alarm and Interlock Control: Each channel can independently set **Alert** (warning) and **Danger** (danger) two-level alarm thresholds. The alarm delay supports programming adjustment from 0 to 10 seconds, capable of filtering out false actions caused by instantaneous signal fluctuations. Each channel corresponds to two passive relay contacts, and the entire system has four alarm contacts. Each contact has a rated load of 250V AC, 3A, and can be directly connected to the on-site sound and light alarm circuit and the unit safety shutdown interlock circuit, achieving graded protection. High-precision signal processing: Utilizing mature signal conditioning, filtering, and linearization circuits, the measurement linear error is ≤ ±0.5% of the full scale, with a minimum resolution of 0.01mm. It can stably capture typical mechanical fault characteristic signals such as rotor imbalance, misalignment of the shaft system, rubbing between moving and stationary components, bearing wear, and oil film turbulence.

Local status display and basic configuration: The front panel is equipped with multiple groups of LED status indicator lights, which can directly display the module's normal operation, channel OK, warning, danger, bypass, power failure, etc. States; combined with operation keys, it can complete basic parameter settings such as alarm threshold, delay, range, and alarm logic configuration locally, without relying on the upper computer.

Strong anti-interference design: The module adopts a metal shielding structure internally, achieving electrical isolation between input, output, and power circuits, which can resist electromagnetic interference (EMI) and radio frequency interference (RFI) generated by industrial site frequency converters, high-power motors, and high-voltage equipment, ensuring the long-term stability of measurement signals in complex working conditions.

System integration and communication: Supports internal bus communication within the 3300 system, allowing for integration with the entire TSI system for centralized status management; compatible with the Bentec System 1 equipment status monitoring software, supporting remote parameter configuration, real-time data acquisition, trend analysis, fault record storage and query, facilitating equipment operation and fault traceability.

Technical Parameters

Measurement Parameters

Channel Quantity: 2 fully independent isolated channels.

Measurement Range: Standard 0~2mm peak-to-peak (customizable).

Sensitivity: Standard 7.87V/mm (compatible with 5mm/8mm probes).

Measurement Accuracy: Linear error ≤ ±0.5% of the full scale, resolution 0.01mm.

Frequency Response: Standard 1~800Hz (optional low frequency 0~500Hz, high frequency 1~1000Hz).

Alarm Delay: 0~10 seconds programmable, factory default 3 seconds.

Probe Compatibility: 3300 XL 5mm or 8mm eddy current probes, extension cables, preamplifiers. Electrical parameters

Power supply: -24V DC (allowable fluctuation ±10%), with safety barrier - 23~-26V DC.

Power consumption: ≤2.5W, maximum working current 12mA.

Input impedance: matched to 3300 XL preamplifier standard input impedance.

Relay output: passive dry contacts, 4 channels (2 channels per channel), rated load 250V AC/3A, 30V DC/3A.

Analog output (optional): 4-20mA or 0-10V DC, accuracy ±0.1% of full scale.

Isolation performance: High voltage electrical isolation between input/output/power supply, anti-common-mode interference ≥2500V AC.

Environmental and mechanical parameters

Operating temperature: -40℃~+70℃.

Storage temperature: -40℃~+85℃.

Relative humidity: 0%~95% (no condensation).

Installation method: 3300 series standard 19-inch rack slot installation, supports hot swapping.

Shell material: Metal panel + flame-retardant engineering plastic, shock-resistant, corrosion-resistant, oil-resistant.

Protection level: IP20 (internal installation in control cabinet).

Size: Standard 3300 module size, compatible with 19-inch rack slots.

Certification and compliance

Industry standards: Compliant with API 670 Rotating Machinery Monitoring and Protection Standard.

Electromagnetic compatibility: CE certification, complies with EN 61000-6-2, EN 61000-6-4 standards.

Explosion-proof rating: Non-explosion-proof design, no built-in safety barrier, only applicable to non-flammable and non-explosive areas.

V. Structural Design

The module adopts a standard rack-mounted modular structure, divided into the front panel, internal main circuit, and rear wiring terminals. The layout is compact and reasonable, facilitating installation, wiring, and maintenance.

Front panel: Integrated power supply, channel OK, warning, danger, bypass, etc. LED indicators, as well as parameter setting keys and display windows. Operators can directly view the module's operating status, alarm information, and complete basic parameter configuration on-site, making the operation simple and convenient.

Internal main circuit: Divided into two completely independent signal processing units, corresponding to two measurement channels. Each unit integrates signal conditioning, filtering, fault detection, alarm comparison, and drive output circuits. There is no electrical connection between channels, ensuring high operational reliability, and a single-point failure does not affect the operation of the other channel.

Rear wiring terminals: Zone layout, clearly dividing two probe input terminals, four relay alarm terminals, power terminals, and system communication interfaces. Terminal markings are clear, wiring is neat, facilitating on-site wiring, troubleshooting, and daily maintenance, reducing the risk of wiring errors.

Hot swapping design: The module and the backplane of the rack use gold-plated connectors, with reliable contact, supporting online insertion and removal. Replacing the module does not require shutting down the entire monitoring system, reducing the impact of maintenance on the unit's operation.

VI. System Compatibility

Hardware compatibility

Rack and power supply: Perfectly compatible with 3300 series standard 19-inch rack, system power module, system monitoring module. Different functions of the same series modules (such as speed module, displacement module) can be installed in the same rack for collaborative work.

Sensing components: Fully compatible with 3300 XL series 5mm/8mm eddy current probes, extension cables, preamplifiers. Components of the same specification can be directly interchanged without recalibration, reducing spare parts costs.

Output connection: Relay contacts can be directly connected to on-site sound and light alarms, unit safety interlock circuits, DCS/PLC system dry contact inputs; Analog output (optional) can be connected to DCS/PLC analog input module to achieve centralized data monitoring.

Software compatibility Configuration software: Compatible with the dedicated configuration software for the Benelli 3300 series, supporting remote parameter configuration, alarm logic editing, data calibration and firmware upgrade.

Monitoring software: Adapted to the equipment status monitoring software for System 1, capable of real-time vibration data acquisition, trend curve display, spectrum analysis, fault record storage, report generation and remote access, facilitating the management of the equipment throughout its lifecycle.

VII. Typical Application Scenarios

Power Industry: Radial vibration monitoring and over-limit protection for steam turbines, gas turbines, generator sets, large feedwater pumps, blowers and fans in thermal power plants, nuclear power plants. Real-time monitoring of rotor vibration changes, warning of imbalance, misalignment, bearing faults, etc., to ensure the safe and stable operation of the main unit.

Petrochemical Industry: High-speed rotating equipment in non-explosion-proof areas such as centrifugal compressors, process turbines, large process pumps, screw compressors, etc. Monitoring of vibration status, avoiding unplanned shutdowns caused by rotor faults, bearing wear, etc., to ensure continuous production.

Metallurgical Industry: Vibration monitoring of blast furnace fans, sintering main exhaust fans, large drive motors, rolling mill transmission equipment, furnace tilting mechanisms, etc. Predicting bearing wear, rotor imbalance, gear meshing faults, etc., to reduce equipment failure rates.

General Industry: Large rotating machinery in industries such as cement, papermaking, light industry, water treatment, etc., such as coal grinding machines, fans, pump sets, compressors, etc. Conducting online condition monitoring, preventive maintenance and safety interlock protection to extend equipment service life and reduce operation and maintenance costs.

VIII. Installation and Maintenance Specifications

Installation Requirements

Frame Installation: Insert the module smoothly into the vacant slot of the 3300 frame, ensure that the gold-plated connector at the rear fully bites and contacts, tighten the panel fixing screws to prevent loosening.

Sensor Wiring: Connect the 5mm/8mm eddy current preamplifier signal cables to the corresponding input terminals according to the channel number. Ensure the wiring is firm without loosening to avoid signal interference or short circuits.

Alarm Wiring: According to the design drawings, connect the relay contact lines to the audible and visual alarm circuit or the unit safety interlock circuit, distinguish between warning and dangerous contacts, ensure correct interlock logic.

Power On Configuration: Confirm that the 24V DC power supply of the frame is normal before powering on. Through the panel buttons or remote configuration software, set the vibration alarm threshold, alarm delay, range and other parameters according to the on-site equipment parameters, and save and activate after setting.

Probe Installation: Strictly follow the specifications. The static gap of the 5mm probe is 0.76mm, the static gap of the 8mm probe is 1.27mm. The probe end face is perpendicular to the surface of the measured shaft, and the cable is well fixed and protected to avoid vibration wear.

Daily Maintenance

Inspection and Check: Regularly observe the status of the panel indicator lights to confirm that the module and channels are running normally; check for any looseness, oxidation, overheating at the connection terminals, and handle potential hazards in a timely manner.

Accuracy Calibration: Regularly use a standard gap calibration device to calibrate the measurement accuracy of the module annually to ensure that the measurement data meets the API 670 standard requirements.

Clean Cooling: Regularly clean the module surface and the dust inside the frame slots to ensure good ventilation and cooling, preventing dust-induced poor cooling, short circuits, etc.

Spare Parts Replacement: When replacing modules, probes or cables, it is necessary to use the original Benelli product of the same model. Do not use non-original accessories to avoid compatibility issues or measurement errors.

IX. Usage Precautions

This module is not explosion-proof and has no built-in safety barrier. It is strictly prohibited to install and use it in flammable and explosive, areas with combustible gases or dust. 

It must be used in conjunction with the 3300 XL series 5mm/8mm standard eddy current sensing system. Do not mix with other probe specifications (such as 11mm), otherwise it will result in mismatched range and sensitivity, and measurement failure. The static installation gap of the probe must be strictly carried out in accordance with the standards. If the gap is too small, it is likely to cause wear and damage between the shaft and the probe. If the gap is too large, it will lead to insufficient signal strength and poor linearity.

It is prohibited to disassemble the module, modify the internal circuitry or change the factory-calibrated length of the sensing cable without authorization. Illegal operations will cause equipment damage and also result in loss of product warranty rights.

Before wiring, maintenance, or module replacement, the power supply of the frame must be cut off to prevent short circuits and electric shock accidents.

The alarm threshold, delay, and other parameters must be strictly set according to the process requirements of the unit. Improper parameters will cause protection failure or frequent false alarms.

The installation position of the module should be as far away as possible from the frequency converter, transformer, high-voltage distribution cabinet and other strong electromagnetic interference sources to reduce the influence of external interference on the measurement signal.