LaMotte LTC3000wi Turbidity & Chlorine Lab Meter - Manual (Page 62)

9. Remove the tube from the
meter. Add one *Chlorine
DPD #3 Instrument Grade
Tablet (6197A). Cap the tube.
Shake for 10 seconds. Invert
slowly 5 times. An increase in
color represents Combined
Chlorine.
NOTE: For wastewater samples, Standard Methods for the Examination
of Water and Wastewater recommends waiting 2 minutes for full color
development when testing total chlorine.
10. Open the meter lid. Insert the
tube into the chamber. Align
the index line on the tube with
the index arrow on the meter.
Close the lid.
11. Press
ENTER
to select Scan
Total Chlorine. The screen
will display Reading... for
about 1 second. The result
will appear on the screen.
Record the result as Total
Chlorine.
Total Chlorine (L)
1.25
ppm
Scan Free Chlorine
Scan Total Chlorine
12:00:00 001/500
12. Subtract the Free Chlorine reading from the Total Chlorine reading
to obtain the concentration of Combined Chlorine.
Total Chlorine - Free Chlorine = Combined Chlorine
*Warning: Reagents marked with an * are considered to be potential
health hazards. To view or print a Material Safety Data Sheet (MSDS)
for these reagents go to www.lamotte.com. To obtain a printed copy,
contact LaMotte by e-mail, phone or fax.
NOTE: For the most accurate results, samples over 6 ppm chlorine
should be diluted with chlorine demand free water and re-tested.
NOTE: The meter will remember the last scanned blank reading. It is not
necessary to scan a blank each time the test is performed. To use the
previous blank reading, instead of scanning a new one, scroll to Scan
Sample and proceed. For the most accurate results, the meter should
be blanked before each test and the same tube should be used for the
blank and the reacted sample.
62
Chlorine Analysis