2150EX AV Flow Module - Isco

2150EX Area Velocity Flow System
Section 3 Programming
Data Storage Settings
General Settings
Changing a Setting
You should also check the Data Storage Rates while you are
reviewing the program settings. You can view the storage rates
on the Data Storage tab to ensure that pertinent types of data
are being stored, and that the rates will provide a sufficient
amount of data for your application. Refer to section 3.3.6 for
instructions on how to modify the data storage rates.
Once the site’s configuration has been resolved, the Site and
Module Names may be changed to help you better manage the
sites and data collection. Giving sites descriptive names such as
“12th and Main Streets” can help you easily recognize the measurement
locations, instead of generic terms such as “Site 1.” Site
and Module Names are discussed in sections 3.3.7 and 3.3.8.
After modifying a setting as described in sections 3.3.2 through
3.3.8, click on the APPLY button (or press F9 on your keyboard).
Flowlink sends the change to the module and updates the site’s
settings in its Flowlink database.
3.3.1 Level A measurement of the actual liquid level must be taken to adjust
the level readings. The value of this measured depth should be
entered on the Level measurement tab in Flowlink.
Measurement Location The location of your measurements can affect the flow conversion
results. An understanding of how the AV Sensor measures level
and velocity will help you determine where the measurements
should be taken.
The AV Sensor transmits an ultrasonic sound wave. It propagates
from the front of the sensor in a cone-shaped pattern. From
within this cone, the AV Sensor measures the stream velocity.
Therefore, it is best to measure level from a point inside the cone.
Since this cone cannot be seen, a general rule is to measure in
front of the sensor along the channel centerline at a distance
equal to the liquid depth. For example, if the stream is one foot
deep, take the level and channel dimension measurements one
foot upstream from the sensor. If the flow at this point is turbulent,
consider relocating the sensor.
Figure 3-2 Preferred Measurement Location
Do not measure the level and channel dimensions right at the
sensor, as the sensor and the mounting ring may cause a slight
“jump” or localized rise in the level. At very low levels and high
velocities, this jump in the liquid surface may become quite significant.
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