LaMotte DC1600 Colorimeter User Manual
Page 18
FREE CHLORINE
1.
Rinse a clean colorimeter tube (0967) with sample water. Fill to the 10 mL line with sample.
2.
Select setting 4 on “Select Wavelength” knob and press “30 Second Read” button.
3.
Insert tube into colorimeter chamber and adjust to 100%T with “Set Blank” knob. This is the 100%T blank.
4.
Remove tube from colorimeter and pour off all but a sufficient amount of sample water to cover a tablet. Add one
*DPD #1 Instrument Grade Tablet (6903). Crush tablet with a tablet crusher (0175), then add water sample until
tube is filled to 10 mL line. Cap tube and shake until tablet has dissolved. Solution will turn pink if free chlorine is
present.
5.
Press “30 Second Read” button and insert tube into colorimeter chamber. Record %T as soon as reading stabilizes.
Reading for free chlorine should be made within 30 seconds.
6.
Consult calibration chart to determine free chlorine concentration in parts per million (ppm). Do not discard sample
if test for total residual chlorine is to be made. If reading is greater than 4.0 ppm, it is recommended that a dilution be
made of the sample and the result multiplied by the dilution factor.
COMBINED CHLORINE
1.
Add one DPD #3 Instrument Grade Tablet (6197) to sample from Step 5 above. Crush tablet with tablet crusher
(0175). Cap tube and shake until tablet dissolves. An increase in color over Step 5 represents combined chlorine.
2.
Press “30 Second Read” button and insert sample into colorimeter chamber. Record %T as soon as reading stabilizes.
3.
Consult calibration chart to determine total chlorine concentration in parts per million (ppm). Subtract free chlorine
reading from total chlorine reading to obtain concentration of combined chlorine. If reading is greater than 4.0 ppm,
it is recommended that a dilution be made of the sample and the result multiplied by the dilution factor.
DC1600 FREE AND TOTAL CHLORINE CALIBRATION CHART
%T
9
8
7
6
5
4
3
2
1
0
90
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
80
0.10
0.11
0.12
0.13
0.14
0.15
0.16
0.18
0.19
0.20
70
0.21
0.22
0.24
0.25
0.26
0.28
0.29
0.30
0.32
0.33
60
0.34
0.36
0.37
0.39
0.41
0.42
0.44
0.45
0.47
0.49
50
0.51
0.52
0.54
0.56
0.58
0.60
0.62
0.64
0.66
0.68
40
0.71
0.73
0.75
0.78
0.80
0.83
0.85
0.88
0.91
0.94
30
0.96
1.00
1.03
1.06
1.09
1.13
1.16
1.20
1.24
1.28
20
1.32
1.37
1.41
1.46
1.51
1.57
1.62
1.68
1.74
1.81
10
1.88
1.95
2.03
2.12
2.21
2.31
2.42
2.54
2.67
2.82
0
2.98
3.17
3.39
3.65
3.96
18