Bently Nevada 74712 Seismoprobe Velocity Transducer

Product Description

The Bently Nevada 74712 Seismoprobe Velocity Transducer delivers precise, non-contact measurement of absolute vibration in rotating machinery. It converts mechanical motion into a voltage signal directly proportional to vibration velocity, enabling reliable condition monitoring and machinery protection. Designed for rugged industrial environments, it withstands harsh temperatures, mechanical shocks, and vibration without compromising performance.

Moreover, the 74712 uses a two-wire moving-coil design, offering higher sensitivity than accelerometer-based velocity sensors. Its compact size and robust construction allow direct mounting to bearing housings, casings, or structural components. This sensor can also integrate with a velocity-to-displacement converter, providing flexible monitoring for critical machinery.

For instance, turbines, compressors, motors, and pumps benefit from continuous monitoring of bearing housings or casings. The Seismoprobe ensures early detection of abnormal vibration trends, reducing the risk of unscheduled downtime and costly repairs. In addition, high-temperature variants expand operational capability for demanding applications.

Key Features

• High sensitivity for detecting abnormal vibration velocity in rotating machinery

• Rugged, hermetically sealed design suitable for harsh industrial conditions

• Two-wire configuration simplifies installation and reduces wiring complexity

• Reliable long-term operation for turbines, compressors, motors, and pumps

• Optional velocity-to-displacement conversion allows flexible measurement modes

• Withstands mechanical shock up to 50 g along non-sensitive axes

• Operational frequency range from 4.5, 10, or 15 Hz up to 1 kHz

Technical Specifications

Model: 74712 Seismoprobe Velocity Transducer
Measurement Type: Absolute vibration velocity (relative to free space)
Design: Two-wire moving-coil sensor
Output Signal: Voltage proportional to vibration velocity
Weight: 0.48 kg
Operating Temperature:

• Standard: -29°C to +121°C (-20°F to +250°F)

• High-temperature variant: -29°C to +204°C (-20°F to +400°F)
  Sensitivity: 20 mV/mm/s (500 mV/in/s), ±5%
  Transverse Sensitivity: ≤10% of axial sensitivity
  Mounting: Direct attachment to bearing housings, casings, or structures
  Shock Resistance: 50 g peak along non-sensitive axis
  Frequency Range: 4.5 / 10 / 15 Hz minimum to 1 kHz maximum, +0, -3 dB typical
  System Components:

• Seismoprobe transducer

• Compatible cable

• Optional velocity-to-displacement converter

Typical Applications

• Continuous vibration monitoring for turbines and compressors

• Motor and pump casing vibration diagnostics

• Machinery protection in power generation and process industries

• Integration with velocity-to-displacement converters for advanced monitoring

• Preventive maintenance and early fault detection programs

FAQ

Q: What type of vibration does the 74712 measure?
A: It measures absolute vibration velocity relative to free space for bearing housings and casings.

Q: Can it operate at high temperatures?
A: Yes, the high-temperature variant handles -29°C to +204°C (-20°F to +400°F).

Q: Is installation complex?
A: No, the two-wire moving-coil design simplifies mounting and wiring.

Q: Can it measure displacement?
A: Yes, when paired with a velocity-to-displacement converter, it provides displacement readings.

Q: Which machinery types are compatible?
A: Turbines, compressors, motors, pumps, and other rotating equipment benefit from this sensor.