Description
Product Overview
The Bently Nevada 330500-00-20 Velomitor is a piezoelectric velocity sensor designed for measuring absolute vibration on bearing housings, machine casings, and other structures. Unlike traditional moving-coil velocity transducers, the Velomitor uses a solid-state design with integrated electronics, making it suitable for continuous vibration monitoring on industrial rotating equipment.
The sensor provides a standardized velocity output with a nominal sensitivity of 100 mV/in/s, or 3.94 mV/mm/s, with a ±5% tolerance. Its velocity measurement range extends to 50 in/s peak, allowing it to monitor vibration from normal operating conditions through higher vibration levels.
The 330500-00-20 configuration is supplied without a mounting thread adapter and uses a 20 ft (6.0 m) configuration identified in the part number specification. The exact mounting arrangement should be checked against the existing installation before replacement.
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Brand | Bently Nevada |
| Model | 330500-00-20 |
| Product Type | Velomitor Piezo-Velocity Sensor |
| Measurement | Absolute vibration velocity |
| Sensitivity | 3.94 mV/mm/s (100 mV/in/s) ±5% |
| Velocity Range | 1270 mm/s (50 in/s) peak |
| Frequency Response | 4.5 Hz to 5 kHz, ±3.0 dB |
| Frequency Response | 6.0 Hz to 2.5 kHz, ±0.9 dB |
| Amplitude Linearity | ±2% to 152 mm/s (6 in/s) peak |
| Transverse Sensitivity | Less than 5% of sensitivity |
| Mounted Resonant Frequency | Greater than 12 kHz |
| Output Bias Voltage | -12 ±3.0 VDC |
| Dynamic Output Impedance | Less than 2400 Ω |
| Mounting Thread Adapter | No adapter |
| Cable Configuration | 20 ft / 6.0 m |
| Maximum Cable Length | Up to 305 m / 1,000 ft with specified cable |
| eBay Condition | New |
Published technical information identifies the 330500-00-20 as a Velomitor piezo-velocity sensor with the specifications above.
How the Sensor Is Used
The sensor is mounted directly to the machine structure being monitored. Mechanical vibration is converted into an electrical signal proportional to vibration velocity, which can then be connected to a compatible vibration monitoring system.
Typical measurement points include:
- Bearing housings
- Motor housings
- Pump casings
- Fan and blower structures
- Compressor casings
- Turbine auxiliary equipment
- Industrial rotating machinery
For machinery protection and condition monitoring, velocity measurement is commonly used to identify changes in overall machine vibration and to provide an early indication of mechanical problems.
Typical Applications
The 330500 series is suitable for continuous vibration monitoring in industrial environments where absolute structural vibration needs to be measured.
Common applications include:
Power Generation
Monitoring pumps, fans, motors, auxiliary turbines, and other rotating equipment.
Petrochemical and Process Plants
Monitoring centrifugal pumps, compressors, cooling equipment, and other process machinery.
Industrial Machinery
Monitoring motors, blowers, fans, pumps, and rotating mechanical equipment.
The sensor’s solid-state construction is particularly useful where reliable long-term vibration measurement is required.
Installation Guide
Proper mechanical mounting is important because the sensor measures vibration transmitted through the machine structure.
Before installation:
- Confirm that the replacement sensor is the same 330500 configuration.
- Check the mounting location and thread arrangement.
- Clean the mounting surface and remove dirt, paint buildup, or corrosion.
- Install the sensor firmly against the machine surface.
- Route the cable away from high-temperature surfaces and sources of electrical interference.
- Verify the sensor wiring before connecting it to the monitoring system.
- Check the output bias voltage and signal after startup.
- Compare the vibration reading with the expected baseline for the machine.
The 330500-00-20 is specified without a mounting thread adapter, so the existing mounting arrangement should be confirmed before ordering a replacement.
Maintenance and Troubleshooting
A velocity sensor can produce abnormal readings because of mechanical mounting problems as well as electrical faults. If the vibration value suddenly changes, do not immediately assume that the sensor itself has failed.
Check the following points:
- Sensor mounting tightness
- Mounting surface condition
- Cable damage
- Connector condition
- Cable routing
- Monitoring-system input
- Sensor output bias
- Changes in actual machine vibration
A loose mounting connection can introduce measurement errors or unwanted resonance. If the sensor output is missing, verify the power and signal circuit before replacing the transducer.
For a replacement sensor, recording the original vibration level before removal is also useful. After installation, compare the new reading with the previous baseline under similar operating conditions.
Replacement and Compatibility Notes
When purchasing a replacement, compare the complete part number rather than only the 330500 series designation.
The 330500-00-20 configuration includes specific options for mounting and cable arrangement. Other 330500 variants may have different mounting adapters, cable configurations, or approval options.
For critical machinery monitoring systems, verify:
- Complete part number
- Cable length
- Mounting thread
- Sensor sensitivity
- Monitoring-system input requirements
- Existing installation arrangement
This helps prevent a physically similar sensor from being installed with an incompatible configuration.
Condition
The referenced eBay listing identifies the item as New. The listing does not identify it as used or refurbished.
For industrial replacement applications, buyers should still compare the sensor nameplate and part number with the existing unit before installation.
Short eBay Title
Bently Nevada 330500-00-20 | Velomitor Piezo-Velocity Sensor
中文简短标题
Bently Nevada 330500-00-20 | Velomitor压电式振动速度传感器
