Hach-Lange 2100 AN Laboratory Turbidimeter Basic User Manual - Manual (Page 13)

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 mode
display shows "01". 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 mode display
shows "00" after the
last vial is measured. 12. Push CAL/Zero.
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).
Turbidity measurement
W A R N I N G
Potential explosion and fire hazard. This instrument is for measuring water based
samples. Do not measure solvent or combustible based samples.
For accurate turbidity readings use clean sample cells and remove air
bubbles.
Measurement notes
Proper measurement techniques are important in minimizing the effects
of instrument variation, stray light and air bubbles. For accurate and
repeatable measurements:
Instrument
• Make sure that the instrument is on a level, stationary surface that is
free of vibration during the measurement.
• The USEPA filter assembly is required for turbidity measurements
reported for United States Environmental Protection Agency (USEPA),
National Primary Drinking Water Regulations (NPDWR) or National
Pollutant Discharge Elimination System (NPDES) permits.
• Turn the instrument on 30 minutes (Ratio on) or 60 minutes (Ratio off)
before measurement. Keep the instrument on 24 hours a day if the
instrument is used regularly.
• Always close the sample compartment lid during measurement,
calibration and storage.
• Remove the sample cell from the instrument and turn off the
instrument if the instrument is stored for an extended time period
(more than a month).
English 13