TESTO 400 Instruction Manual page 37

5 Make the required settings and click
on Next.
For volume flow measurement as per the DIN EN 12599 standard, it is
necessary for the measurement to be carried out at different measuring
points. The number of measuring points depends on the distance from
the point of discontinuity and irregularities in the profile.
6 Configure the measuring interval for each measuring point in the duct.
7 Click on Start.
The longer a measuring point is measured, the more accurate the result
at the end of the volume flow measurement as per DIN EN 12599.

During the measurement in the duct, the required immersion depth of
the next measuring point is automatically shown on the display. The
immersion depth of the probe can be found on the scale of the probe
shaft.
9 Operation
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