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FKS 1DP- PBM-E User Manual - Copyright © 2018 FlowKinetics
LLC, All Rights Reserved
21
The speed indicated by the FKS series instrument is corrected by multiplication by
K (for a non-unity Pitot Static probe). The instrument automatically performs this
correction after storage of the factor K.
Taking Measurements with the FKS Series
CAUTION: The FKS series are not suitable for use with toxic or corrosive
gases or for liquid pressure measurement.
Measurement starts with attachment of Silicone or Tygon
tubing to the Pitot
Static probe and the pressure transducer barbs. The P+ connection barb of the
transducer is connected to the Total pressure port of the Pitot probe, and the Static
pressure port of the Pitot probe is connected to the transducers P- barb
connection.
The Pitot probe can then be carefully inserted into the airflow. It may be necessary
to drill holes into the ducting for insertion.
Pitot Static Probe Duct Surveys
If average duct speeds, or volumetric flow rates are required, it is necessary to
perform a Pitot traverse of the duct. This involves taking measurements at various
positions across the duct. Before a traverse is conducted, it is necessary to select
a suitable location to perform the survey. If possible, avoid traverses close to fans,
dampers pipe bends, expansions etc. Try to survey at least 8 duct diameters
downstream of the aforementioned elements and 2 duct diameters upstream of
these elements. The survey is performed with the aid of Fig. A1. Either the
Centroids of Equal Areas
or
Log-Tchebycheff
point distribution may be used. A
survey proceeds as follows:
1.
Decide on the number of survey points and then mark these on the
Pitot probe using a marker or adjustable spring clips (present on
some Pitot Static probes).
2.
At the selected survey location, drill two perpendicular holes in the
duct (for a round duct) or the desired number of holes for a
rectangular duct, ensuring sufficient hole clearance to safely insert
the Pitot Static probe.
3.
Carefully insert the Pitot Static probe into the duct and position at the
first traverse location. Ensure that the Pitot Static probe is aligned
with the axis of the duct using the alignment guide on the probe as a
reference.
4.
Wait for the readout on the display to stabilize. The FKS meter has
sophisticated routines for taking measurements in unsteady flows.
Either adaptive averaging or exponential averaging/smoothing can
be used (averaging only in the Pitot routine). If the readings are still