Hach-Lange 2100 AN IS Laboratory Turbidimeter User Manual - Manual (Page 17)

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 17 and Optical system check on page 17.
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.
Measure the Gelex stray light standard
Measure the Gelex stray light standard when the instrument is first received. Record the value on the Gelex vial with a permanent marker one time.
1. Clean the stray light
standard with a soft,
lint-free cloth to remove
water spots and
fingerprints. 2. Apply a small bead
of silicone oil from the
top to the bottom of the
vial. 3. 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. 4. Push RANGE to
select automatic
ranging.
"AUTO" is shown below
the Range Mode label
on the instrument. 5. Push SIGNAL AVG
to turn signal averaging
off.
The SIGNAL AVG light
turns off. 6. Push UNITS/Exit to
select the NTU
measurement mode.
English 15