OPERATOR AND UNIT MAINTENANCE MANUAL
(INCLUDING REPAIR PARTS AND SPECIAL TOOLS LIST)
FOR WATER QUALITY ANALYSIS SET: PURIFICATION (WQAS-P)
DESCRIPTION AND USE OF CONTROLS AND INDICATORS FOR TURBIDITY METER
To maximize battery life the display is automatically switched off after 4 minutes of non-use. To reactivate the display,
simply press the ON/OFF key.
A. Turn the meter on by pressing the ON/OFF key.
B. The meter will carry out a self-test displaying a full set of figures. After the test, the LCD will change to the
C. When the LCD displays "----" the meter is ready to measure.
D. Fill a clean cuvette up to one-quarter inch (0.5 cm) from its rim with the thoroughly agitated
sufficient time for bubbles to escape before securing the cap.
Note: do not over tighten the cap.
E. Wipe the cuvette thoroughly with a lint-free tissue before inserting into the measurement cell. The cuvette
must be completely free of fingerprints and other oil or dirt, particularly in the area where the light goes
through (approximately the bottom 2 cm/1 inch of the cuvette).
Place the cuvette into the cell and check that the notch on the cap is positioned securely into the groove.
G. The mark on the cuvette cap should point towards the LCD.
H. Press the READ/⇑ key and the LCD will display a blinking "SIP" (Sampling in Process). The turbidity value
will appear after approximately 25 seconds.
Samples exceeding 40 FTU* Standard Methods require dilution. In such cases, the correct amount of
turbidity standard, 0 FTU or turbidity-free water to be added to the sample can be calculated as follows:
Vos = 3000/T
Vos = volume of sample (ml) to be combined with turbidity standard, 0 FTU to obtain the final
volume of 100 ml.
T = Turbidity Meter reading (exceeding 40 FTU*)
E.G.: Turbidity Meter reading = 200 FTU*
3000/200 = 15 ml (Vos)
15 mL (Vos) + 85 ml (turbidity standard, 0 FTU) = 100 ml.
At this point, take a sample of this solution and measure turbidity. The correct turbidity value of the
original sample will be:
Tη x 100 ml/Vos = Tα
Where: Tη = new Turbidity Meter reading
Tα = actual turbidity value of the original sample
If Tη = 27 FTU*
Tα = 27 FTU* x 100 mL/15 ml = 180 FTU*
*1 FTU = 1 NTU
HOW TO ENSURE ACCURATE MEASUREMENTS
Each time the cuvette is used, tighten the cap to the same degree.
Discard the sample soon after the reading is taken to avoid permanently clouding the glass.