JDC Electronic SA EasyFlow User Manual
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Before starting the acquisition
Before starting the acquisition, make sure that the probe has reached the water's temperature. The water
salinity is directly dependent on the water temperature which is measured to correct the salinity and thus bring
it to a standard 20° C. Just use the Multimetre mode to control the temperature stability.
Quantity of injected salt
For good results, this fine instrument requires a salinity increase of 10% or at least 15 mg per litre compared
with the natural salt content of the water course. The acquisition of a complete measurement curve ensures
good gauging. The quantity of salt to be injected should be known with precision since it is a factor for the water
flow calculation.
The quantity of injected salt should be well known because it will be used to
calculate the flow rate. The recommended quantity of 5 to 20 g per litre/second of
water flow depends on the distance to point of injection necessary for a good
mixture. The longer the distance, the bigger the tracer dilution and then the
smaller the increase in salinity in the gauging area.
The EasyFlow allows salt injection from 10 g to 100 kg. The available salt quantities are the following:
10, 20, 50, 100, 200 and 500 g, 1, 2, 5, 10, 20, 50 and 100 kg.
Select the salt quantity with the button SELECT and confirm by pressing ENTER.
Measuring interval
After the salt quantity, the button SELECT permits to choose the interval between measurements.
Choosing the interval between 1, 2, 4 or 8 seconds is directly related with the laps
of time the salt cloud needs to completely pass by the gauging site. The total
disposable memory for one gauging site being 1000 measurements the interval may
allow data acquisition during ¼ hour, ½ hour, 1 hour or 2 hours.
It is important to adapt the interval to the characteristics of the water course. Rapid and turbulent waters
mixing and spreading the tracer rapidly allow rapid data acquisition and the injection of the tracer at shorter
distance from the gauging area. In this case a shorter interval is chosen. If instead the volume of the water flow
is high, the distance to the tracer injection point will be long and the time for the tracer cloud to pass by the
gauging site will be longer. The interval will have to be longer as well. Experience in gauging with tracers will
make the choice of sites and gauging parameters easier. Once the choice has been made, press ENTER.
At this moment all necessary parameters for a good gauging has been introduced in the device and the
acquisition can begin.
Beginning of the acquisition
After the start of the data acquisition, the EasyFlow begins the measurements
according to the programmed interval. At each measurement, salinity and water
temperature are displayed on screen. These measurements are checked to detect
the arrival of the salt cloud.
For correct operation, the device should do at least 30 measurements before the arrival of the salt cloud.
In case where more than 100 measurements have been done before the arrival of the salt cloud and to prevent
wasting memory space, the device will only conserve the last 100 measurements. So, the memory cannot be full
before the arrival of the salt cloud.
As soon as the salt cloud has been detected, the display shown here appears.
Instead of the now useless temperature indication, the initial salinity "IS" is
displayed. At the end of the acquisition procedure, the salinity should have reached
again this initial value. On the second line is always displayed the actual salinity "S".