Description
Key Technical Specifications
| Parameter | Value |
|---|---|
| Model Number | 3500/44M (176449-03) |
| Manufacturer | Bently Nevada (Baker Hughes) |
| Product Type | Aeroderivative GT Vibration Monitor |
| Input Channels | 4 independent channels |
| Sensor Compatibility | Velomitor sensors, accelerometers via Aero GT I/O modules (86517, 86497) |
| Keyphasor Inputs | 2 separate Keyphasor signals |
| Power Consumption | 7.7 W typical |
| Input Impedance | >95 kΩ (Prox/Accel); 3.5 MΩ (Velomitor) |
| Frequency Response | 4 Hz to 30 kHz (-3 dB, direct signal) |
| Accuracy | ±0.33% of full-scale (typical) |
| Operating Temperature | -30°C to +70°C |
| Sensitivity Options | 3.94 mV/(mm/s), 5.71 mV/(mm/s), 10.19 mV/(m/s²), 2.55 mV/(m/s²), 1.02 mV/(m/s²) |
| Filter Options | Signal Integration, 1X Vibration Tracking, Band-pass |
| Alarm Configurations | Up to 8 sets of alarm parameters per channel (multimode) |
| Mounting | 3500 rack, 1 front slot + 1 rear I/O slot |
Product Introduction & Supply Chain Strategy
The BENTLY 3500/44M 176449-03 is a purpose-built 4-channel vibration monitor for aeroderivative gas turbine applications . It is specifically optimized for high-speed, variable-speed turbines such as the GE LM1600, LM2500, LM5000, LM6000, and Rolls-Royce RB211 and Avon. The module interfaces with Velomitor sensors and accelerometers through dedicated Aero GT I/O modules, providing continuous vibration monitoring with programmable alarm setpoints for Alert and Danger conditions. It accepts input from two separate Keyphasor signals, allowing each channel pair to use a different tracking filter — critical for capturing 1X vibration across the wide speed range typical of aeroderivative turbine starts and transients . The module supports three filter options: Signal Integration, 1X Vibration Tracking, and Band-pass Vibration . It is designed to meet the vibration protection requirements of API 670 and is certified for SIL 2 applications .
Procuring this module as New Surplus is a TCO-critical decision for any facility operating aeroderivative gas turbine packages. Refurbished or used vibration monitors carry unacceptable risk: degraded signal conditioning accuracy, compromised input impedance from prior overvoltage events, and latent sensor power supply damage that no functional test can guarantee. A failed 3500/44M means no vibration data, no 1X tracking, and no protection relay actuation on a high-value aero turbine. The unplanned downtime cost from a turbine trip or, worse, a failure to trip dwarfs the module’s value. This unit offers OEM-origin traceability, zero operational hours, and a 1-year warranty — eliminating the uncertainty of used or repaired components.
- 3500/44M 176449-03
- 3500/44M 176449-03
Installation & Configuration Guide
Stage 1: Pre-Installation (Prep & Safety)
- Lock out and tag out the 3500 rack. De-energize the rack power supply. The 3500/44M supports hot-swap replacement in systems with redundant power supplies; for single-supply configurations, full power-down is required.
- Wear ESD wrist strap. Gather a camera for documentation.
- Critical: Record the existing module’s configuration from the 3500 Rack Configuration Software. Document the sensor type (Velomitor vs. accelerometer), filter mode (Integration, 1X Tracking, or Band-pass), Keyphasor settings, alarm thresholds (Alert and Danger per channel), and mode-switching logic (up to 8 sets). Document the I/O module type in the rear slot.
Stage 2: Removal
- Disengage the module retaining screws at the top and bottom of the faceplate.
- Gently pull the module straight out from the backplane connector using the extraction handles. Do not rock side-to-side.
Stage 3: Installation
- Align the new module with the guide rails.
- Press firmly and evenly until fully seated into the backplane connector.
- Secure with the retaining screws.
Stage 4: Configuration & Verification
- Re-energize the rack power.
- Observe LED status: OK should illuminate; TX/RX should indicate communication; Bypass should remain off .
- Critical: The module configuration resides on the 3500 rack CPU module. The rack will automatically push the existing configuration. However, always verify the configuration using the 3500 Rack Configuration Software before returning to service.
- Inject simulated sensor signals to verify measurement accuracy and alarm thresholds. Test each channel independently.
Firmware/Software Versions & Upgrade Notes
The 3500/44M works with onboard firmware governed by the 3500 Rack Configuration Software and the rack CPU module. The module configuration — including sensitivity, filter mode, and alarm setpoints — is stored on the rack CPU, not on the 3500/44M itself. Upon replacement, the rack pushes the existing configuration to the new module.
Version compatibility note: The 176449-03 is the specific spare part number for the 3500/44M main processor module The “M” designation indicates compatibility with the current M-series architecture and System 1 condition monitoring software. Verify your 3500 rack firmware version is compatible with the 3500/44M module.
Critical warning: Ensure the correct rear I/O module is installed (Aero GT, Prox/Velom, or Multimode Prox/Velom) to support the required sensor type. Incorrect I/O module pairing will result in measurement errors or no signal.
Frequently Asked Questions (FAQ)
Q: Why is this New Surplus cheaper than Bently Nevada list price but more expensive than refurbished units?
A: The price reflects sourcing verified, OEM-origin new units from global inventory. You avoid the OEM’s full retail margin and the hidden failure risk of refurbished stock — degraded signal conditioning, compromised input impedance, and latent sensor power supply damage. The cost of a single aeroderivative turbine protection failure dwarfs the price difference.
Q: What is the difference between 176449-03 and 3500/44M?
A: The 3500/44M is the complete model designation for the Aeroderivative GT Monitor. The 176449-03 is the specific Bently Nevada spare part number for the main processor module card.
Q: What turbines is this module designed for?
A: The 3500/44M is designed for aeroderivative gas turbines, including GE LM1600, LM2500, LM5000, LM6000, Rolls-Royce RB211 and Avon, and United Technologies Turbo Power GG3, G44, FT4, and FT8.
Q: Can I use this module for standard centrifugal pumps or steam turbines?
A: No. The 176449-03 is optimized specifically for aeroderivative gas turbines with high-speed, variable-speed operation and dual Keyphasor tracking. For standard industrial machinery, use the Bently Nevada 3500/42M Proximitor/Seismic Monitor .
Q: Does this module support hot-swapping?
A: Yes, in systems with redundant power supplies. However, removing the module suspends vibration protection for the associated four channels. Always follow site-specific safety protocols before replacement.
Q: Does replacement require reloading configuration parameters?
A: No. The configuration resides on the 3500 rack CPU module and is automatically pushed to the new 3500/44M. However, verify the configuration using the 3500 Rack Configuration Software before returning to service.
Q: What sensors are compatible with this module?
A: The module interfaces with Velomitor sensors and accelerometers through Bently Nevada Aero GT I/O modules (86517 and 86497). Ensure the correct I/O module is installed in the rear slot .
Q: What is the warranty period and coverage?
A: The module carries a standard 1-year warranty against manufacturing defects. Coverage applies to the module hardware — not field wiring, sensor faults, or installation damage. All units are QC-tested before shipment to verify signal conditioning, communication handshake, and alarm threshold accuracy.
Start Chat
