Description
Bently Nevada 3500/70M (176449-09)
Technical Specifications:
- Module Type: Keyphasor signal generator for the 3500 rack
- Input: Proximity probe signal from 3300 XL series eddy current sensors
- Output: Once-per-revolution keyphasor pulse to the 3500 backplane
- Communication: Via 3500 backplane; data accessible through TDI or communication gateway modules
- Power Requirements: Powered from the 3500 rack backplane
- Operating Temperature: -30°C to +65°C
- Storage Temperature: -40°C to +85°C
- Dimensions (H × W × D): 241.3 mm × 24.4 mm × 241.8 mm
- Weight: Approximately 0.91 kg
Functional Features:
- Generates a precise once-per-revolution timing pulse from a proximity probe input
- Provides phase reference for synchronous vibration analysis and rotor balancing
- Enables forward/backward precession identification in orbit plots
- Supports order tracking and phase-sensitive monitoring across the 3500 system
- Compatible with 3300 XL proximity probe sensor systems
- Integrates with 3500/40M, 3500/42M, and other monitor modules for comprehensive vibration analysis
- Front-accessible module replacement with hot-swap capability
- System 1 software connectivity for advanced diagnostics and trending
Application Scenarios:
- Steam turbines, gas turbines, and turboexpanders requiring phase-referenced vibration monitoring
- Centrifugal and reciprocating compressors for rotor balancing and orbit analysis
- Generators and large motors for synchronous vibration tracking
- Gearboxes for gear mesh frequency analysis with phase reference
- Any rotating machinery application requiring once-per-revolution timing for advanced diagnostics
- API 670 compliant machinery protection systems
Performance Parameters:
- Input Signal: Proximity probe gap voltage from 3300 XL sensor system
- Output Signal: Keyphasor pulse synchronized to once-per-revolution marker
- Frequency Response: Compatible with 0 to 10 kHz proximity probe signals
- Alarm Response: Configurable Alert and Danger thresholds
Material Composition: Industrial-grade electronic components housed in a standard 3500 rack module enclosure with front-accessible connector interface
Structural Features: Single-slot front plug-in monitor occupying one 3500 rack slot. The module connects to a proximity probe through the rear I/O terminal block or direct wiring. Front panel includes status LEDs for operational diagnostics.
Working Principle: The module receives a proximity probe signal containing the once-per-revolution marker (typically from a keyway, notch, or raised key on the shaft). The internal circuitry detects the marker pulse, conditions it, and generates a clean keyphasor output pulse that is distributed through the 3500 backplane to all monitor modules. This pulse serves as the angular reference for phase-sensitive vibration measurements, enabling the system to construct orbit plots, identify unbalance angles, and perform order tracking analysis.
Installation Requirements:
- Install in a Bently 3500 rack within an IP-rated cabinet
- Connect a 3300 XL proximity probe mounted at a keyway or notch on the shaft
- Ensure proper probe gap voltage setting (typically -10 Vdc ± 0.25 Vdc)
- Use shielded cables for probe wiring with proper single-point grounding
- Route signal cables away from high-voltage power cables and EMI sources
- Configure the keyphasor channel through 3500 configuration software
Usage Notes:
- The keyphasor probe must be mounted at a location with a clear once-per-revolution marker on the shaft
- Verify probe gap voltage before commissioning
- De-energize circuits before servicing
- Observe ESD handling procedures for module swaps
- The 3500/70M does not provide independent alarm outputs; it serves as a timing reference for other monitor modules
- Ensure the keyphasor signal is properly configured in all dependent monitor modules
