JDC Electronic SA EasyFlow User Manual
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MADD
Technologies sàrl
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Tel: +41 24 445 31 16 – Fax: +41 24 445 21 23 – Email: [email protected] – www.madd.ch
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• Upon arrival at the measurement site, place immediately the probe into the water. It will then reach fast
the water temperature.
• Try to position the probe in a place where the water course is not too turbulent. Always avoid the
phenomenon of cavitation around the probe. It can perturb the measurements and cause air bubbles
between the probe's electrodes.
• Before starting an acquisition, verify that the probe is at the waters temperature.
• Don’t forget that the EasyFlow must record at least 30 measurements prior to the arrival of the salt
cloud. The time needed for these measurements is proportional to the gauging intervals as shown below:
INTERVAL
RECORDING BEFORE CLOUD ARRIVES
1 second
30 seconds
2 seconds
1 minute
4 seconds
2 minutes
8 seconds
4 minutes
• It is preferable to dilute the salt in water taken from the river to be gauged and then inject the total mixed
solution at once into the water course (max. 300 g of salt per litre). Avoid not yet dissolved salt to sink to
the bottom of the riverbed.
• The most important point for successful gauging is in fact the good dissolution and mixture of the salt in
the water course. Some turbulence caused by a few stones or tiny waterfalls favours the mixing process.
In a straight and flat riverbed or a canal placing some stones can help the mix.
• Small side streams of the water course and basins may slow down part of the current which does not
favour the mixing process.
• A higher speed of the current is a positive factor for the mixing process and a rapid passage of the salt
cloud favours the measuring since the threshold of natural salinity varies very little.
• Gauging in tunnels, straight canals with a current speed of 1 meter/second gives good results even at long
distances (e.g. more than 3000 m) from point of salt injection.