Description
The 3500/44-02-01 is a specialized, full-height, 4-channel monitoring module designed specifically for the Bently Nevada 3500 Machinery Protection System. Unlike standard proximity or seismic monitors, this module is engineered to handle the unique, high-frequency, multi-component vibration profiles characteristic of aeroderivative gas turbines (such as LM2500, LM6000, or RB211 variants).
It interfaces directly with high-temperature velocity transducers and accelerometers to track casing and bearing vibrations, providing continuous machinery protection while isolating real turbine faults from background combustor noise or structural resonance.
The part number breakdown for the -02-01 suffix specifies:
- -02 (I/O Module Type): 4-Channel Aeroderivative I/O Module with Internal Terminations
- -01 (Agency Approval Option): CSA/NRTL/C (Class 1, Division 2, Groups A, B, C, and D)
Technical Specifications
| Parameter | Specification / Value |
| Brand | Bently Nevada (Baker Hughes) |
| Model Series | 3500 Series Machinery Protection |
| Part Number Configuration | 3500/44-02-01 |
| Inputs | 4 channels accepting interface velocity or acceleration sensors |
| Transducer Compatibility | Bently Nevada 330750, 330752, or specific high-temperature charge amplifiers |
| Signal Processing | Integrated independent tracking filters bound to Keyphasor references |
| Frequency Range | Dependent on sensor configuration; up to 10 kHz processing bands |
| Accuracy | Within ±1.0% of full scale for vibration amplitude metrics |
| Front Panel Interfaces | 4 coaxial buffered output connectors (unfiltered raw signals) |
| Backplane Current Draw | 700 mA at 5 V DC; 100 mA at 24 V DC |
| Operating Temperature | −30 to +65 °C (−22 to +150 °F) |
Field Application and System Integration Notes
Specialized Tracking Filters
Aeroderivative gas turbines operate with flexible, lightweight rotors and high casing-to-rotor weight ratios, making casing vibration data highly complex.
- Keyphasor Interlocking: The 3500/44-02-01 utilizes tracking filters synchronized with the 3500/25 Keyphasor inputs. This allows the module to extract the precise 1X (synchronous) and 2X vibration components relative to individual rotor speeds (e.g., HP and LP shafts on multi-spool turbines).
- Signal Discrimination: By locking onto the rotor speed, the module filters out broadband combustion noise, cross-talk from adjacent machinery, and blade-pass frequencies that would otherwise cause false trip signals on standard wide-band monitors.
Internal Termination Wiring Advantages
The -02 option indicates the module relies on an internal termination I/O structure.
- No External Blocks: Field wiring lands directly on the terminal connectors of the rear-mounted I/O module, eliminating the need for an external companion Field Termination Assembly (FTA) or terminal strip.
- Shielding Rules: For high-temperature charge amplifiers or velocity transducers (like the 330750), verify that cable shielding is terminated cleanly at the 3500 rack ground bar to prevent electrostatic noise induction from the turbine ignition systems.
Monitoring Configuration Limits
Configuration must be completed using the 3500 Rack Configuration Software. The configuration profile dictates whether channels operate independently or are paired for multi-axis monitoring.
- Warning: Ensure that the specific sensor scale factor matches the output of your intermediate charge amplifier or velocity transducer (e.g., 200 mV/in/s or 100 pC/g) before making the protection loops live. Mismatched scale profiles will invalidate the Alert/Danger trip matrix.
Commercial and Procurement Data
- Product Condition: New Original (Factory Sealed) or Certified Refurbished Legacy Surplus (includes multi-channel validation and frequency sweep test certificates).
- Standard Warranty: 12-month comprehensive depot hardware warranty.
- Estimated Lead Time: Typically ships within 2 to 4 business days from warehouse stock.
- Pricing Notice: Prices are subject to current market availability, global component constraints, and specific Class 1 Div 2 regional safety tracking parameters. Contact our engineering sales desk for an official, itemized commercial quote.
