Overview

The Bently Nevada Velomitor Piezo-Velocity Sensor is designed to measure absolute (relative to free space) vibration on bearing housings, casings, or structures. The 330500 model is a specialized piezoelectric accelerometer that integrates solid-state electronics for enhanced reliability and performance.

Specifications

Electrical Characteristics

• Sensitivity: 3.94 mV/mm/s (100 mV/in/s) ±5%
• Frequency Response:
  • 4.5 Hz to 5 kHz (270 cpm to 300 kcpm), ±3.0 dB
  • 6.0 Hz to 2.5 kHz (360 cpm to 150 kcpm), ±0.9 dB
• Temperature Sensitivity: -14% to +7.5% typical over the operating temperature range
• Velocity Range: 1270 mm/s (50 in/s) peak
• Transverse Sensitivity: Less than 5% of sensitivity
• Amplitude Linearity: ±2% to 152 mm/s (6 in/s) peak
• Mounted Resonant Frequency: Greater than 12 kHz
• Output Bias Voltage: -12 ±3.0 VDC, referenced to Pin A over temperature
• Dynamic Output Impedance: Less than 2400 Ω
• Broadband Noise Floor (4.5 Hz to 5 kHz): 0.004 mm/s (160 μin/s) RMS, nominal
• Grounding: Case isolated

Cable and Environmental Specifications

• Maximum Cable Length: 305 meters (1,000 feet) of cable (part number 02173006) with no degradation in signal quality
• Operating Temperature Range: -55°C to 121°C (-67°F to 250°F)
• Shock Survivability: 5,000 g peak, maximum
• Relative Humidity: Up to 100% non-submerged; case is hermetically sealed

Additional Characteristics

• Base Strain Sensitivity: 0.005 in/s/mstrain
• Magnetic Field Susceptibility: < 51 min/s/gauss (at 50 gauss, 50-60 Hz)

Physical Specifications

• Weight: 142 grams (5.0 oz) typical
• Diameter: 25.3 mm (0.995 in)
• Height: 63.2 mm (2.49 in)
• Case Material: 316L stainless steel
• Connector: 2-pin Mil-C-5015, hermetically sealed, 316L stainless steel shell
• Mounting Torque: 32-46 kg cm (24-40 in-lb) max
• Polarity:
  • When the sensor case motion is toward the connector, Pin A becomes positive relative to Pin B

Output Characteristics

• Inrush Current: 3 Amps supplied for 10 ms without ESCP trip
• Output Voltage Drop: 0.3 V DC maximum
• Steady-State Overcurrent Trip: 5 Amps typical per point
• Output Leakage Current: 0.1 mA maximum
• On Response Time: 0.5 ms maximum
• Off Response Time: 0.5 ms maximum
• Protection Features:
  • Short-circuit protection
  • Overcurrent protection
  • Overtemperature protection
  • Auto recovery for all protection mechanisms