Description
Bently Nevada 3300/55-01-04-02-02-01-00-06-00
Technical Specifications:
- Probe Diameter: 25mm
- Linear Range: 12.7mm (500 mils)
- Sensitivity: 0.787 V/mm (20 mV/mil)
- Frequency Response: Suitable for slow-changing differential expansion signals
- Operating Temperature: Extended range for steam turbine environments
- Compatibility: Compatible with legacy 7200 DE sensor system output
Functional Features:
- Extended 12.7mm linear range for large differential expansion measurements
- Designed specifically for steam turbine rotor-to-casing thermal growth monitoring
- Full interchangeability of probe, extension cable, and Proximitor within the 3300 XL 25mm system family
- ClickLoc gold-plated brass connectors lock into place preventing connection loosening
- CableLoc design provides 330N (75 lb) pull strength on cable-to-probe connection
- TipLoc patented molding ensures robust bond between probe tip and body
- FluidLoc cable option prevents oil or liquid leakage through cable interior
- Compatible with 3500 monitoring system modules
- RFI/EMI immunity meeting CE electromagnetic compatibility standards
Application Scenarios:
- Differential expansion measurement on medium to large steam turbine generators
- Rotor-to-casing thermal growth monitoring in power generation turbines
- TSI (Turbine Supervisory Instrumentation) system integration
- Applications where thermal expansion differential exceeds 2mm and requires extended linear range
- Steam turbine startup, shutdown, and load change monitoring
Performance Parameters:
- Measurement accuracy: ±5% of full scale
- Resolution: Sub-millimeter level
- Temperature stability: Maintains accuracy across full operating temperature range
- Dynamic range: Covers slow-changing thermal expansion signals
- Signal-to-noise ratio: High, with built-in anti-interference design
Material Composition:
- Probe housing: AISI 304 stainless steel
- Probe tip: High-performance polymer material
- Connector: Gold-plated brass ClickLoc connectors
- Cable: Shielded coaxial construction with optional FluidLoc sealing
Structural Features:
- 25mm probe diameter for extended linear range
- Available in armored and unarmored versions
- Thread options for versatile mounting on turbine casing
- Proximitor available in DIN-rail mount or panel mount configurations
- SpringLoc terminal strips on Proximitor for tool-free field wiring
Working Principle:
The Proximitor generates a high-frequency oscillating current (1–2 MHz) through the 25mm probe coil, creating an alternating electromagnetic field at the probe tip. When a conductive metal target enters this field, eddy currents are induced on the target surface. These eddy currents generate a counter magnetic field that changes the effective impedance of the probe coil. The impedance change is directly proportional to the gap distance between the probe tip and the target surface. The Proximitor demodulates this impedance change and outputs a DC voltage signal linearly proportional to the gap, enabling precise non-contact displacement measurement over the extended 12.7mm range.
Installation Requirements:
- Mount probe using appropriate threaded housing with locknut and safety wire
- Set initial gap at midpoint of 12.7mm linear range
- Verify Proximitor output voltage at calibrated gap position
- Use extension cable length matching Proximitor system length designation
- Route signal cables at least 30 cm away from power cables
- Apply connector protectors or self-fusing silicone tape on all probe-to-cable connections
- Ground cable shield at one end only to prevent ground loops
Usage Notes:
- All three components (probe, cable, Proximitor) must be from the same 3300 XL 25mm system family
- Verify target material is ferromagnetic steel (AISI 4140 calibration standard)
- Do not use self-fusing silicone tape in turbine oil environments
- Perform gap verification every 6 months or after major maintenance
- Proximitor output voltage must remain within linear range
- For hazardous area installations, select the appropriate agency approval option
- When upgrading from 7200 DE system, verify monitoring system software compatibility
