Thermo Fisher Scientific C101 Colorimeter - Manual (Page 14)

Measurement: Chlorine, Free & Total
C401/301/201Colorimeter
10
7. Remove the vial from the meter and add into it the content of one
Chlorine, Free (DPD) Reagent Sachet (for Free Chlorine
determination) or the content of one Chlorine, Total (DPD) Reagent
Sachet (for Total Chlorine determination).
8. Replace the cap, ensuring it is screwed on finger tight to the vial.
Invert the vial repeatedly for approximately 20 seconds, until the
powder has dissolved.
Note: A small amount of the powder may remain un-dissolved in the vial, but
this will not affect the measurement.
Add content of one Chlorine, Free (DPD) Reagent Sachet
(for Free Chlorine determination) or one
(for Total Chlorine determination).
Chlorine, Total
(DPD) Reagent Sachet
Invert vial approximately 20
seconds until powder dissolves
9. Gently push the vial back fully into the sample well of the meter,
whilst again aligning the ▼ mark on the vial with the ▲ mark on the
meter.
10. For Free Chlorine determination, press the READ/ENTER key within
two minutes from the time the DPD Free reagent was added to the
vial.
11. For Total Chlorine determination, wait for two minutes and then press
the READ/ENTER key within four minutes from the time the DPD
Total reagent was added to the vial.
12. The meter will flash either [CL-F] or [CL-T], depending on which test
is being performed, whilst the measurement is taken. It will then
display the Chlorine concentration in parts per million (ppm) Cl
2
.
Free
Chlorine
Sample
READ
ENTER
ppm
Free Chlorine determination