Bently Nevada Seismoprobe Velocity Transducer Systems

The Bently Nevada Seismoprobe Velocity Transducer Systems are engineered to measure absolute vibration (relative to free space) of bearing housings, casings, or structures. These two-wire systems consist of a transducer and the necessary cable, utilizing moving-coil technology to provide a voltage output proportional to the vibration velocity.

Specifications

Electrical Specifications:

• Sensitivity:
  20 mV/mm/s (500 mV/in/s) ±5%, when properly terminated and oriented according to the calibration angle.

• Calibration Load:
  10 kΩ (Terminal "A" to "B"). The output is measured across pins "A" and "B".

• Temperature Sensitivity:
  0.2%/°C.

• Frequency Response:

  • 4.5 to 1000 Hz (270 to 60,000 CPM), ±3 dB typical.
  • 10 to 1000 Hz (600 to 60,000 CAM), ±3 dB typical.
  • 15 to 1000 Hz (900 to 60,000 CPM), ±3 dB typical.

  The frequency response ranges from the minimum operating frequency to 1 kHz (60,000 CPM), ±3 dB typical. Please consult Bently Nevada for detailed calibration data.

• Dynamic Operating Range:
  Maximum displacement of 2.54 mm (0.100 in) peak-to-peak.

• Velocity Range:
  25 mm/s (1 in/s) at +22°C of casing vibration at 100 Hz with a 10 kΩ load.

• Coil Resistance:
  1.25 kΩ ±5%.

• Locked Coil Inductance:
  125 mH (typical).

• Amplitude Linearity:
  ±5% from 0.01 to 5.0 in/s (0.254 to 127 mm/s) at 100 Hz (6000 CPM).

• Shock Resistance:
  Withstands a peak acceleration of 50 g along the non-sensitive axis.

• Transverse Sensitivity:
  ±10% of the sensitive axis sensitivity at 100 Hz and 1.0 in/s (2.54 cm/s).

• Polarity of Output Signal:
  Pin A goes positive with respect to Pin B when the transducer case velocity is towards the connector.

• Lead Wire Length:
  Maximum length of 305 meters (1,000 feet) between the Seismoprobe Velocity Transducer and a 3300 or 3500 Monitor. Please refer to the manual for frequency roll-off at longer lengths.

Environmental Limits:

• Operating and Storage Temperature:
  • Model 9200: -29°C to +121°C (-20°F to +250°F).
  • Model 74712: -29°C to +204°C (-20°F to +400°F).

Mechanical Specifications:

• Case and Adapter Material:
  Anodized aluminum (A204).

• Gasket Material:

  • Model 9200: Neoprene.
  • Model 74712: Silicone.

• Connector Material:

  • Top and Side Mount Options: Cadmium-plated aluminum, neoprene, and silver-plated copper.

• Terminal Block Option:
  Polyphenylene Sulfide with nickel-plated copper contacts.

• Mounting Torque:
  Various mounting base options:

  • 1/2-20, 1/4-20, 1/4-28, 5/8-18, or M10X1: 5.6 N·m (50 in·lb).
  • 8-32 threaded studs: 1.41 N·m (12.5 in·lb).

Physical Specifications:

• Height:
  102 mm (4 in) typical, depending on the connector option.

• Diameter:
  41 mm (1.6 in) typical.

• Weight:

  • Model 9200: 300 grams (10.5 ounces) typical.
  • Model 74712: 480 grams (17 ounces) typical.