Thermo Fisher Scientific C101 Colorimeter - Manual (Page 45)

Calibration: Chlorine, Free & Total, Chlorine Dioxide, Bromine, Ozone
C401/301/201/103/104/105 Colorimeter
41
instrument, whilst aligning the ▼ mark on the vial with the ▲ mark
on the meter.
7. Press the ZERO key to blank the meter to that vial; the meter will
display [ZERo] whilst this is taking place.
8. Remove the blanking vial from the meter. The meter displays 4.1
ppm, with the CAL annunciator on the top left corner.
9. Use the MODE key repeatedly to select the concentration of the
prepared calibration standard in the 4.1 - 5.0 ppm range.
Blanking
Sample
CAL
MODE
ZERO
CAL
ppm
Press Mode to
select calibration
point from 4.1 ppm
to 5.0 ppm in an
incremental circular
manner.
10. Select another clean vial, un-screw the cap and fill it with 10 ml of
the prepared Chlorine standard (fill up to the line on the vial).
11. For Free Chlorine or Chlorine Dioxide calibration, select a Chlorine,
Free (DPD) Reagent Sachet, whereas for Total Chlorine, Bromine
or Ozone calibration, select a Chlorine, Total (DPD) Reagent
Sachet. Open the sachet and tip the contents into the
vial containing the calibration standard.
12. 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.
13. Insert the vial fully into the sample well of the meter, whilst again
aligning the ▼ mark on the vial with the ▲ mark on the meter.
14. For Free Chlorine or Chlorine Dioxide calibration, press the
READ/ENTER key within two minutes from the time the sachet was
added to the vial. As for Total Chlorine, Bromine or Ozone
calibration, wait for two minutes before pressing the READ/ENTER
key and this has to be done within five minutes from the time the
sachet was added to the vial.
15. The meter will display [--Rd--] whilst the calibration standard is
being measured and then displays [SAVE] to prompt for calibration
acceptance and saving of calibration data.
Free
Chlorine
Sample
4.5 ppm
ppm
READ
ENTER CAL