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according to the above guidelines. It is possible, however,
for leak sounds to be outside of the expected filter settings so
a more systematic, 2-stage process is recommended:
1. Select all available filters and survey the system for
any leak sound. When potential leak sound is detected,
continue pre-location with all filters active until the
loudest area of sound is located. Go to the Filter Selection
screen (Figure 12) and see what specific frequency (or
frequencies) is most active.
2. Set the HL 5000 so that only the 2 or 3 frequencies
showing the most activity are selected (Section 3.5.2). Return to
the areas where the suspected leak sound was loudest and
measure the leak sound level using the selected filters. The point
at which the filtered leak sound is loudest, pinpoints the
location of the leak.
3.7 Mute button
Pressing the mute button on the control panel one time
places the HL 5000
in stand-by mode. When the unit is in
standby mode, no sound is passed through to the headphones and
no sound measurements are taken. Pressing the button a
second time returns the unit to listening/measurement mode, at
which time the displayed values on the Main Screen are updated.
Caution:
Even careful placement of the microphone can result in
extremely loud sounds in the headphones. To protect the
hearing of the operator, it is recommended that headphones
be muted before moving the microphone.
