JDC Electronic SA SalinoMADD - Manual (Page 9)

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MADD Technologies sàrl
– Avenue des Sports 42 – CH-1400 Yverdon-les-Bains – Switzerland
Tel: +41 24 445 31 16 – Fax: +41 24 445 21 23 – Email: [email protected] – www.madd.ch
The SalinoMADD will automatically calculate the precise values of the 4 measured calibration points. It will
furthermore determine the curve's non-linearity and calculate necessary corrections. All these parameters are
saved provisionally and the screen passes on to the following display.
This display specifies the end of the calibration of the salinity. At this
moment is still possible to abort the calibration procedure by pressing
If the calibration is ok, confirm by pressing ↵. This will store the
calibration data and these will be maintained even during the exchange
of batteries.
Either command SAVE or ABORT will return to MAIN MENU.
Preparing doses for calibration
Although your SalinoMADD supplier can supply calibration doses, it is useful to be in a position to prepare own
doses, particularly when salt other than chloride sodium is chosen.
The necessary material
• A precision scales with 0,1 g graduations, accuracy < 0,1 %.
• A glass measure with volume scales, accuracy < 0,1 %.
• A number of small plastic bottles with a content of at least 20 ml each
• A pipette or syringe 20 cc accurately calibrated
• An adequate quantity of salt for water flow gauging
• 1 liter of demineralised water with a conductivity not exceeding 10 μS/cm or a resistivity of at least
100'000 ohms.
The preparation of doses
• Weigh out precisely 13,2 g of salt and pour it into a glass.
• Add demineralised water to make up 1 liter of solution
• Stir it well in order to obtain a homogenous solution
• Using a pipette, transfer the solution into small plastic bottles by doses of 20 ml
Each dose will contain: (13,2 g / 1000 ml) * 20 ml = 264 milligrams of salt , added into 200 ml of pure
water, which results: 200+20=220 ml of water containing 264 milligrams of salt .
Then: 264 mg / 220 ml * 1000 = 1200 milligrams of salt per litre .
WARNING
The gauging accuracy depends on the precision of the calibration, which depends on the precision of the
preparation of calibration doses described above. A deviation of only 0,1 gram from the required weight of salt
results in a gauging error of 0,75 %. A deviation of 10 ml from the required volume of water results in a gauging
error of 1 %.
Under certain circumstances and for practical reasons, smaller or bigger doses of calibration liquid may be
needed, but the quantity of salt will always have to be proportional to the total quantity of solution, e.g. : 6,6
grams of salt for 0,5 litre solution or 26,4 g of salt into 2 litres solution. Or if you want to use 10 grams of
salt, you have to add pure water up to a total of 757,5 ml of solution.