Lovibond CHECKIT Comparator Bedienungsanleitung Seite 5

Combined chlorine
Deduct the reading for free chlorine from the figure obtained
for total chlorine. The difference represents the result for
combined chlorine.
Example:
minus : free chlorine
gives :
Total chlorine - direct (DPD No. 4 (R)-tablet)
 Fill both cells to the 10 ml mark and  place one cell in the
left-hand compartment of the comparator as a blank.  Place
one DPD No. 4 (R)-tablet in the other cell, close it with a lid and
 swirl it until the tablet is dissolved.  Place this second cell
in the right-hand compartment of the comparator and  wait
for 2 minutes reaction time.  Then compare the two colour
fields against north daylight and read off the result as total
chlorine in mg/l.
Note:
Levels of chlorine above 10 mg/l can cause bleaching of the
sample.
Important:
Place the cell with the mark (point) to the viewer in the com-
partment.
It is essential to rinse the cells thoroughly after each test.
To obtain maximum accuracy always view and match colour
against north day light.
Store CHECKIT Disc in the dark.
®
total chlorine
combined chlorine
1.20 mg/l
0.42 mg/l
0.78 mg/l
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