13
4 Measuring
Please note the following when measuring:
z
Ensure that there is
firm contact
between the device and the
object of examination. However, do not exert any pressure on
the probe tip.
z
Always measure until you have a clear impression of the meas-
urement location.
4.2.1
What you need to know about the noise picked up
If the device is switched on, you will hear noise through the head-
phones. If a measurement is not underway (e. g. when carrying the
device around whilst it is switched on) irregular interference noise
will dominate. If the probe tip is placed on an object of examina-
tion, a steady ambient noise will immediately become audible.
If
you measure close to a leak, the sound of the noise will still
be steady, but it will be much louder and clearer than at an
intact measuring point.
To ensure reliability when analysing noise, you may have to prac-
tise listening (see Section 3.3).
4.2.2
What you need to know about the measured value
displayed
The measured value shown in the display dur-
ing a measurement (here: 859) indicates the
current minimum value
of the noise intensity.
Values above the minimum value will not be
displayed.
When the measurement is complete the device
will show the
minimum value over the entire
measurement
(here: 361).
The calculated minimum sound level is a
relative
value, which
only becomes meaningful when it is compared with measured
values from other measuring points.
The current measured value is always shown with the minimum
value of the previous measurement (here: 007) to help you com-
pare two successive measurements.
