eutech-instruments chloride epoxy Manuel D’Utilisation

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Instruction Manual 
 
Chloride Electrode 
 
5
5. 
Eutech Chloride Standard, 1,000 ppm Cl
-1
, Code no. EC-SCS-CL2-BT. To prepare this 
solution from your own laboratory stock, add 1.65 grams of reagent-grade sodium 
chloride, NaCl, to a one liter volumetric flask about half-full of distilled water. Swirl the 
flask to dissolve the solid. Fill to the mark with distilled water, cap, and upend the flask 
several times to mix the solution. 
 
6. 
Eutech Chloride Standard, 100 ppm Cl
-1
, Code no. EC-SCS-CL3-BT. To prepare this 
solution from your own laboratory stock, add 0.165 grams of reagent-grade sodium 
chloride, NaCl, to a one liter volumetric flask about half-full of distilled water. Swirl the 
flask to dissolve the solid. Fill to the mark with distilled water, cap, and upend the flask 
several times to mix the solution. 
 
 
GENERAL PREPARATION 
 
Electrode Preparation 
 
Remove the rubber caps covering the electrode tips and the rubber insert covering the filling hole of 
the reference electrode. Fill the combination electrode or the reference electrode with the filling 
solution shipped with the electrode to a level just below the fill hole. No preparation is required 
with a sealed reference electrode. Connect the electrodes to the proper terminals of the meter as 
recommended by the meter manufacturer. 
 
Electrode Slope Check (with pH/mV meter) 
(Check electrodes each day)  
 
1. 
To a 150 ml beaker, add 100 ml of distilled water and 2 ml of ISA. Place the beaker on a 
magnetic stirrer and begin stirring at a constant rate. After assuring that the meter is in the 
mV mode, lower the electrode tips into the solution. 
 
2. 
Using a pipet, add 1 ml of 0.1M or 1,000 ppm chloride standard to the beaker. When the 
reading has stabilized, record the millivolt reading. 
 
3. 
Using a pipet, add 10 ml of the same chloride standard used above to the beaker. When the 
reading has stabilized, record the millivolt reading. 
 
4. 
Determine the difference between the two readings. A difference of -57±3 mV indicates 
correct electrode operation, assuming the solution temperature is between 20
o
 and 25
o
C.  
See the 
TROUBLESHOOTING 
section if the potential change is not within this range. 
 
Slope is defined as the change in potential observed when the concentration changes by a factor of 
10.