V901 Seismograph

The V901 Seismograph is designed and manufactured by Vibrock to meet the needs of our consultancy services and subsequently our clients.

The V901 is a battery powered portable vibration monitor, purpose designed for measuring blasting, piling, demolition, construction and traffic vibrations.  It can also measure air overpressure from blasting using the optional microphone.

Battery life is up to 3 weeks for continuous 24 hour monitoring.

Results can be downloaded to a PC, where they can be analysed printed and saved using the software supplied.  The V901 Seismograph is also available as a twin channel transducer instrument, enabling measurements on a common time base in two places at once.

A standard 50m extension cable is supplied with the twin channel seismograph.  The V901 seismograph also comes with the option of a built in thermal printer to provide single or multiple printouts of events, on site.

In addition, the V901 seismograph can be configured to support a Vibration Dose Value (VDV) transducer either as a single unit or as one channel of the twin version to enable concurrent VDV and PPV measurements.

The V901 Twin Channel Seismograph, with landline modem kit

The V901 range of Seismographs can be connected to either a landline or GSM modem. This enables the customer to access the V901 from their offices to alter the setup of the Seismograph or to interrogate and download the Seismograph’s memory.

V901 Seismograph Specification

The V901 seismograph’s technical specification is the same as that of the field portable unit but without the on-board printer.

  • Impulse mode for blast monitoring
  • Continuous mode for piling, rail and road traffic monitoring
  • Tri-axial geophone sensor – Option for second tri-axial sensor


  • triggering from 0.1 mm/s
  • single range from 0.1 mm/s to 200 mm/s
  • auto record length from 2 to 18 seconds (in impulse mode)
  • automatic graph scaling
  • Can trigger and record PPV acceleration or displacement parameters
  • Air overpressure from 100 to 140 dB
  • Memory for about 300 events or 30 days continuous recording
  • Battery operated, uses 2 Alkaline ‘D’ cells (or external 12 volt supply). Supplied with shoulder bag
  • Built-in timer function
  • Instant readout and review of memory event results on LCD
  • Download to PC with supplied RS232 cable and Windowsª based software


    • Two stage audible and visible alarm (see below for further information)
    • Solar panel
    • Modem
    • Second Tri-Axial Geophone Pack
    • Vibration Dose Value Transducer with VDV weighting filters
    • Battery Operated Portable Printer (pictured)

V901 Two Stage Audible Alarm

The two stage audible alarm, which also has high intensity strobe beacons, can be used with our V901 and V801 Seismographs. The alarm comes complete with a standard 10 metre extension cable and a battery charger (with LED indication).
By using the seismograph’s setup menu, the customer can set a low and high alarm level to activate the alarm when the ground vibrations detected by the seismograph are approaching (or exceeding) site/safety limits.
The on/off switch is used to switch the siren on and off. It does not switch off the actual alarm.