Description
Bently Nevada 3300/65-03-01-00-00-01-00
Technical Specifications:
- Full-Scale Range: 0 to 15 mils (0–400 µm)
- Relative Transducer Input: 3300 or 7200 Proximitor
- Agency Approval: CSA/NRTL/C certified
- Safety Barrier: External with Velocity Seismoprobe
- Seismic Transducer: Seismoprobe, epoxy-sealed
- Trip Multiply: None
Functional Features:
- Provides four distinct measurements from a single monitor:
- Shaft relative vibration — proximity probe measurement of shaft vibration relative to bearing housing
- Bearing housing vibration — seismic measurement of bearing housing vibration relative to free space
- Shaft absolute vibration — vector summation of shaft relative vibration and bearing housing vibration
- Shaft average radial position — proximity probe DC gap measurement relative to bearing clearance
- Designed for machines with fluid film bearings where significant shaft vibration is transmitted to the casing
- Vector summation algorithm combines proximity and seismic signals for true absolute vibration measurement
Application Scenarios:
- Large steam turbines and gas turbines with fluid film bearings
- Machines where significant vibration energy is transmitted from shaft to casing
- Applications requiring absolute shaft vibration measurement for machinery protection
- Power generation turbines requiring comprehensive vibration assessment
Performance Parameters:
- Full-scale range: 0–15 mils (0–400 µm)
- Measurement types: 4 simultaneous outputs
- Signal processing: Vector summation of relative and casing vibration
Material Composition:
- Electronic monitoring circuitry in industrial enclosure
- Compatible with standard Bently Nevada proximity probes and Seismoprobes
Structural Features:
- Standalone monitor unit
- Input terminals for proximity transducer and seismic transducer
- Relay outputs for alarm and trip functions
- Epoxy-sealed relay construction for harsh environment protection
Working Principle:
The Dual Probe Monitor receives two simultaneous inputs: a proximity probe signal measuring shaft vibration relative to the bearing housing, and a seismic velocity transducer signal measuring bearing housing vibration relative to free space. The monitor performs vector summation of these two signals to calculate true shaft absolute vibration — the vibration of the shaft relative to free space. This is critical for large turbines where casing vibration contributes significantly to the total shaft motion observed in absolute terms.
Installation Requirements:
- Install proximity probe and seismic transducer on the same machine axis
- External safety barriers must be ordered separately
- Configure full-scale range and alarm setpoints per application requirements
- Connect to 3300 or 7200 series Proximitor for relative vibration input
Usage Notes:
- CSA/NRTL/C approval is only available with relays when the monitor is ordered as part of a system
- Verify whether the target machine transmits significant vibration to the casing before selecting this monitor
- Engineering services are available from Bently Nevada to determine machine vibration transmission characteristics
- External safety barriers must be properly specified and installed separately
