Hach-Lange 2100 N Laboratory Turbidimeter User Manual - Manual (Page 15)

7. Use the oiling cloth
to apply the oil equally
to the surface of the
vial. Remove the
excess oil. Make sure
that the vial is almost
dry. 8. Put the vial in the
sample cell holder with
the triangle on the vial
aligned with the
reference mark on the
sample cell holder.
Close the cover. 9. Push ENTER.
The instrument display
counts down, then
measures the standard.
The next expected
standard (e.g., 20.00) is
shown. The S1 light
turns on. 10. Remove the vial
from the sample cell
holder. 11. Do steps 5–10 for
the other StablCal vials
(from lowest to highest
NTU standard).
The S0 light turns on
after the last vial is
measured. 12. Push CAL.
The instrument saves
the new calibration data
and goes back to
Measurement mode.
StablCal standards storage
• Do not move a StablCal standard to a different container for storage.
Keep StablCal standards in the plastic case provided with the cover
closed.
• Store at 5 to 25 °C (41 to 77 °F).
• For long-term storage (more than one month between use), keep at
5 °C (41 °F).
Using Gelex secondary standards
The Gelex secondary standards are used when a calibration check or an
optical system check is done. Refer to
Calibration verification
on page 16 and Optical system check on page 16.
Gelex notes
• Measure the Gelex secondary standards on the instrument on which
they will be used. The measured values can only be used for one
instrument due to small differences in glass and instrument optical
systems.
• Do not keep a Gelex vial in the instrument for more time than is
necessary to complete measurement. The heat from the lamp can
change the turbidity value of a Gelex vial.
• Keep the Gelex standards at room temperature. Do not let Gelex
standards freeze or become warmer than 50 °C (122 °F). High
temperatures may cause Gelex suspensions to divide.
• Make sure that the Gelex standards are at ambient instrument
temperature before measurement.
English 13