ProMinent DULCOTEST DT1B Operating Manual page 24

Analysis methods
13. Hold the dropping bottle upright
and by slow pressing, add equal
sized drops into the cuvette:
6 drops ➨ DPD 1 buffer sol‐
n
ution
2 drops ➨ DPD 1 reagent
n
solution
Fill the cuvette up to the 10 ml
marking with the water sample
14. Close the cuvette using the cuv‐
ette lid
15. Mix the contents of the cuvette
by tipping it back and forth
16. Position the cuvette in the
sample chamber
ð Observe the correct posi‐
tioning of the cuvette
17. Press the key
[METHOD] flashes for
ð
approximately 3 seconds.
The display value
of free chlorine plus chlorine
dioxide appears in the dis‐
play.
18. Remove the cuvette from the
sample chamber
19. Hold the dropping bottle upright
and by slow pressing, add equal
sized drops into the cuvette:
3 drops ➨ DPD 3 solution
n
20. Close the cuvette using the cuv‐
ette lid
21. Mix the contents of the cuvette
by tipping it back and forth
24
[ZERO/TEST]
[A] = sum
22. Position the cuvette in the
sample chamber
ð Observe the correct posi‐
tioning of the cuvette
23. Switch the countdown on, see
Ä „ Switching the countdown
function on" on page 14 . To do
this, press the
[ZERO/TEST] key
ð Wait for the 2 minutes reac‐
tion time to elapse
[METHOD] flashes for approxi‐
24.
mately 3 seconds.
ð The display value
of free chlorine plus com‐
bined chlorine plus chlorine
dioxide appears in the dis‐
play.
25. Calculation:
Chlorine dioxide (mg/l) =
n
display value
Free chlorine (mg/l) = dis‐
n
play value
[G]
value
Combined chlorine (mg/l) =
n
display value
play value
[!] and
[C] = sum
[G] x 1.9
[A] minus display
[C] minus dis‐
[A]