WAVECONTROL SMP2, Руководство пользователя

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Weighted Peak Method (available for probes WP400 or
WP400-3 )
In the area of low frequencies considered here, which affects a wide variety of
industrial processes, it is normal to find complex non-sinusoidal signals that
are difficult to measure.
The Weighted Peak Method (WPM) is the most appropriate method to obtain
the best results. There are other methods, such as the multifrequency fields
summation method, which may give gross overestimates, since they fail to
take signal phase into account.
WPM performs inverse digital filtering, using a function that is the complement
or inverse of the reference limits curve that we wish to use (selectable).
This gives a result directly as a percentage (%) of the limits for which we are
measuring exposure.
The SMP2 offers an extensive list of limits corresponding to the different
standards or laws of different countries. You can use WPM for any existing
limits.
Weighted measurements using WPM can be taken with any of the three
measurement methods mentioned above. All you need to do is select the
reference limit from the list of available limits, then take the measurement as
indicated for each method. To choose a limit, select “LIMIT” on the dynamic
menu, as shown in the figure screenshot 4A.
The figure screenshot 4B below shows the weighted result for the broadband
electric field in respect of the “Low AL” limits of Directive 2013/35/EU.
With the limit chosen, you can assess the EMF by ensuring that both the peak
and the RMS value are below 100%. Please note that the Peak value, given by
the SMP2 , is already divided by Square of 2 for a direct reading to comply with
the limits.
User’s Manual Electromagnetic Field Meter SMP2 P. 76