System information

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Blastware Compliance Module
Blastware Operator Manual 4–45
NOTE: Due to the processing power and decimal accuracy of a PC, performing VDV calculations
using the Blastware Human Exposure tool on a computer will typically produce a higher accuracy
result when compared to the VDV recorded in the field by the Minimate Pro unit. These results
will typically be within 5% of each other.
a. Frequency Weighting File
Select the Frequency Weighting File that is appropriate for the duration of time that you
are recording data. The weighting file is defined in the standard; it is important to select
the correct geophone channel (Tran, Vert, and/or Long) to monitor:
Frequency Weighting Files
BW6841WB Vertical whole-body vibration, lying down, standing or sitting
BW6841WD Horizontal whole-body vibration, lying down, standing or sitting
BW6841WE Rotational whole-body vibration , lying down, standing or sitting
BW6841WF Vertical whole-body vibration, for motion sickness
BW6841WG Vertical whole-body vibration in buildings
ISO2631WM Whole-body vibration in buildings
b. Calculate (T, V, L)
Based on the VDV standards that you are using as a guideline, select the channels that you
want to monitor, T (Tran), V (Vert) , or L (Long), or any pair. The unit memory is
capable of storing 24 hours of data using one geophone and two channels, at the default
sample rate of 512 s/s.
(3) Interval
The Interval setting is reserved for Histogram and Histogram Combo record modes. The
Histogram Interval is the period of time the monitor records Event information before applying
the data analysis processing. For each interval, the monitor calculates the maximum negative
peaks, the frequency of the largest peak, and up to two peak vector sums. For each channel the
maximum peak and its frequency are calculated. The peak vector sum is calculated over the entire
Event.
(4) Record Stop Mode
The Record Stop Mode sets how the monitor stops recording after being triggered. Choose a
record stop mode if you are using the single shot or continuous record modes. You can choose
between a Fixed Record Time setting or an Auto Stop Mode setting. Fixed Record Time sets
the record time to a specified length. Once the record time has elapsed, the monitor stops
recording. In Auto Record, unlike the Fixed Record Time, the monitor continues to record Event
activity as long as that activity remains above the trigger level (sufficient memory and battery
power must be available). Recording stops a specified period of time after the Event activity falls
below the trigger level. The specified period of time, called the Auto Window, can be adjusted.
Use the Auto Record mode if you are unsure of the actual Event duration.
To choose a Record Stop Mode, position the mouse pointer on the Recording Stop Mode drop–
down menu and click the mouse button. Choose Fixed Record Time or Auto Stop Mode.
(5) Sample Rate
The monitor records using sample rates; 512 (typically for VDV), 1024, 2048 and 4096. The
choice of a Sample Rate depends on the type of monitoring you are conducting. Increasing the
Sample Rate increases the accuracy of the waveform recording. For this reason, set the Sample
Rate according to the location of the standard transducer or the Minimate Pro. For close-in or
near field monitoring, set the Sample Rate to 4096 samples per second. For far-field monitoring,
set the Sample Rate to 1024 samples per second. Increasing the Sample Rate also increases the
amount of memory required to store Events and reduces the number of Events that can be stored
on the monitor. It also reduces the battery life.