ADS Environmental Services FlowShark HV QR 775005 A2 - Manual (Page 17)

ADS FlowShark HV O&M Manual 17
Note: If acclimation and stabilization do not occur within 5 minutes, please
contact an ADS representative for further assistance.
The sensor has been calibrated for measuring velocity in water. However, if velocity
measurements will be taken in another kind of medium in which the speed of sound
differs from that of water (4872 feet per second (1485 mps) at 20°C (68°F)), contact
ADS for assistance in modifying the calibration factor accordingly when setting the
parameters.
Note: Placing the sensor into the flow before turning on the unit may
expedite the temperature acclimation process.
Positioning the Sensor in the Flow
Align the sensor probe parallel to the axis of the pipe/canal. Use the bubble level
attached to the telescoping rod to align the probe horizontally.
Properly positioning the sensor in the flow is essential to obtaining accurate velocity
measurements. Even a slight error in angle can produce errors in velocity readings.
For example, an angle error of 5° will lead to a measurement error of 0.4%; a 10%
angle error will result in a 1.5% measurement error.
Taking Velocity Readings
When immersed in the flow in a pipe or channel, the FlowShark HV measures and
displays the localized, current peak velocity. It also can provide an average, or mean,
of the peak velocity over a specific period of time.
The first (top) row on the control unit display shows the current peak velocity. The
second row displays the current operating temperature read through the temperature
sensor in the probe. Select the up arrow key (
) to view the current raw frequency
and voltage readings from which the velocity and temperature readings are calculated.
The third row displays the average peak velocity, and the fourth row displays the time
period over which the average peak velocity has been calculated.
Calculating Average (Mean) Peak Velocity
To view the average of the peak velocity over a defined period of time, select the
down arrow key () to initiate the velocity average calculations and then select the
same key again after the desired time period has passed. The FlowShark HV displays
and updates the average velocity following each consecutive reading based on the
cumulative readings taken since the down arrow key was originally selected. The
average velocity displayed represents a “running” average and continues until the
down arrow key is selected again. The last average velocity reading and associated