Grundfos DIT-M, Installation And Operating Instructions Manual

Page: 24 / 36

English (GB)
24
7.8.4 In the absence of chlorine
7.9 Chlorine dioxide analysis (ClO
2
,
chlorite, Cl
2
free, Cl
2
combined)
0.01 - 6 mg/l
7.9.1 Important notes
This analysis is used for differentiated determination of:
• chlorine dioxide
• chlorite
• free chlorine
• combined chlorine
The measurements are performed with method "100 Chlorine"
and differentiation "free" as the photometer doesn’t supply a
specific method for the
determination
of these parameters. The
values determined during
measurement
(see section
7.9.2 Measurements ) are not the effective quantities of certain
parameters. The effective quantities have to be calculated out of
the determined values after measurement. (See section
7.9.3 Calculation )
12. Press the [Test] key.
13. Remove the vial from the sample
chamber, empty the vial, rinse vial and
cap several times. Fill with a few drops of
the water sample.
14. Add one DPD No. 1 tablet
(No 95727747 ) straight from the foil and
crush the tablet using a clean stirring
rod.
15. Add water sample to the 10 ml mark.
16. Close the vial tightly with the cap and
swirl gently several times until the tablet
is dissolved.
17. Place the vial correctly in the sample
chamber. See fig. 4 .
18. Press the [Test] key.
19. Remove the vial from the sample
chamber.
20. Add one DPD No. 3 tablet
(No 95727750 ) straight from the foil to
the same water sample and crush the
tablet using a clean stirring rod.
21. Close the vial tightly with the cap and
swirl gently several times until the tablet
is dissolved.
22. Place the vial in the sample chamber
correctly. See fig. 4 .
23. Press the [Test] key. Wait for a reaction
period of 2 minutes.
When the reaction period is finished, the
measurement starts automatically.
The result is shown in the display in:
chlorine dioxide in mg/l chlorine
or
chlorine dioxide in mg/l ClO
2
– mg/l free chlorine
– mg/l combined chlorine
– mg/l total chlorine
1. Fill a clean vial (
∅
24) with 10 ml of the
water sample. Close tightly with the cap.
2. Place the vial correctly in the sample
chamber. See fig. 4 .
3. Press the [Zero] key.
4. Remove the vial from the sample
chamber and empty it, leaving a few
drops in the vial.
5. Add one DPD No. 1 tablet
(No 95727747 ) straight from the foil and
crush the tablet using a clean stirring
rod.
6. Add water sample to the 10 ml mark.
7. Close the vial tightly with the cap and
swirl gently several times until the tablet
is dissolved.
8. Place the vial in the sample chamber
correctly. See fig. 4 .
9. Press the [Test] key.
The result is shown in the display in:
chlorine dioxide in mg/l chlorine
or
chlorine dioxide in mg/l ClO
2
Zero accepted
prepare T 1
press TEST
T 1 accepted
prepare T 2
press TEST
T 2 accepted
prepare T 3
press TEST
Countdown
2:00
*,** mg/l free Cl
*,** mg/l comb. Cl
*,** mg/l total Cl
*,** mg/l free ClO
2
[Cl]
*,** mg/l free ClO
2
1 2 0
prepare Zero
press ZERO
Zero accepted
prepare Test
press TEST
∅
24
*,** mg/l free ClO2 [Cl]
*,** mg/l free ClO2
Caution
The values of tolerance (see section 7.2 Table of
methods and reagents ) apply to the individual
measurement. For calculation with multiple values,
be aware of error propagation!
1 0 0