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Appendix G.
Standards with Frequency Weighting
Some standards can be used with frequency weighting. If frequency
weighting is disabled (OFF), a transient will be triggered if a peak
becomes larger than the configured trigger level, independent of the
frequency.
However, when frequency weighting is active, the trigger level will be
referred to as a percentage-value, relative to the selected frequency
weighting curve.
G1. Example with Standard 51
For standards 51A and 51B, there are two versions of frequency
weighting, Drywall and Plaster, see Figure G1:
•
Drywall: 0.75 in/s
(4 – 15 Hz)
•
Plaster: 0.50 in/s
(2.6 – 10 Hz)
Figure G1. Frequency weighting curves for the standards S51A and
S51B (ISEE Seismograph).