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Profound Vibra and Vibra+ Tri-Axial Vibration Meters

The Profound Vibra series of Vibration Meters are specifically designed for construction and demolition site work. The Vibra makes continuous monitoring of construction/demolition vibration a practical reality to which the Vibra+ adds alarm and data e-mails via an on-board GPRS modem for off-site notification of the exceedance of limits and access to data. Easy to use and rugged, these meters use geophones to directly measure PPV (peak particle velocity) and they also provide acceleration levels. The instruments have amazing battery life (up to 4 weeks on 3 alkaline D cells) and the data is logged against the real time clock in the instruments’ huge memory. The measurement period is user-selectable and the dominant frequency component is recorded for each period PPV. Measurements can be taken continuously or only during user-specified periods and/or only above a user-specified vibration level. The instruments can also save the waveforms of the highest, (up to) nine noise events per hour.

The Vibra+ has all the features of the Vibra and it can additionally send out alarms and data e-mails using the on-board GPRS modem. The frequency content of waveforms downloaded from the Vibra+ can be analysed using FFT analysis and the detection of dominant frequency can also be on an FFT basis (which is more accurate than the zero-crossing method employed by the Vibra). The Vibra+ also measures displacement which can be important for low frequency vibration.

  • Logs Peak Particle Velocity (PPV) and Peak Particle Acceleration (PPA) in 3 dimensions continuously or only during user-specified periods and/or only above a user-specified vibration level
  • Logs dominant frequency of the maximum PPV for each measurement period
  • Captures time traces of the velocity waveform (stores up to 9 traces per hour)
  • Rugged construction makes Vibra ideal for monitoring on construction sites
  • Flexible and practical geophone mounting options
  • The measurement period is programmable from 1 second to 999 seconds and the system will store up to 37800 sets of full results (this equates to more than 3 weeks for measurement periods of 1 minute or more)
  • Frequency range from below 1 Hz – 100 Hz (digital processing extends the frequency range – unprocessed typical geophone responses tail off sharply below about 4.5 Hz and this can result in an underestimate of potentially damaging low frequency vibration)
  • Measures up to 100mm/s
  • Frequency range and accuracy in accordance with DIN 45669:1995 Class 1
  • External alarm beacon available
  • Full PC analysis software provided as standard with each Vibra


Additional Features of the Vibra +

  • The Vibra+ can send out an e-mail on its GPRS modem when a user-selected trigger level is exceed
  • The alarm e-mail contains a summary of the data since the last alarm e-mail
  • The Vibra+ can send out a daily data e-mail with all the results (except the waveform traces)
  • Method of determination of dominant frequency is user-selectable (zero-crossing or FFT)
  • Downloaded waveform traces can be frequency analysed using FFT
  • Peak displacement recorded for each channel in addition to velocity and acceleration
  • FFT narrowband analysis used to determine the dominant frequency of the maximum PPV.
  • Peak displacement recorded for each channel
  • Trace Recorder – the Vibra+ can provide a continuous output to a PC via the USB port (the output is triaxial velocity levels at a sampling frequency of 1024 Hz)