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LP 2000
displays several different codes and messages to help the
user to operate the meter more efficiently.
This indicates that the meter is in a ready
state and measurement or calibration can be
performed.
This indicates that the calibration mode is
active. If the CAL key is not pressed within 6
seconds, the meter will automatically revert
back to the measurement mode.
This indicates that the calibration date setting
mode is active.
This indicates that a 0 FTU standard calibra-
tion solution is required.
This indicates that a 10 FTU standard calibra-
tion solution is required.
This indicates that a 500 FTU standard cali-
bration solution is required.
This blinking SIP (Sample In Progress) mes-
sage indicates that the instrument is being
calibrated.
This shows the last calibration date (MM.DD).
This indicates that the sample is being ana-
lyzed.
This indicates that an error occurred during
calibration (e.g. a wrong standard was used).
Repeat the calibration with fresh standards.
LCD AND ERROR CODES
TIPS TO OBTAIN ACCURATE CALIBRATION
•
All glassware that comes into contact with standards should be
kept clean. Wash with
HI 93703-50
cleaning solution and rinse
with
HI 93703-0
or turbidity free water.
•
Rinse the cuvette twice with 5 mL of the sample, to remove any
previous liquid, dust or foreign matter that may be present.
Gently pour the liquid down the side of the vial to reduce air
bubbles (no mixing is required when Hanna standards are used).
•
Before inserting the vial into the meter,
wipe it clean with
HI93703-70
or a soft,
lint-free tissue. Handle vials so that no
fingerprints are left on the areas where
light passes through (bottom 2 cm).
STANDARD SUSPENSION
Presently, there are only two recognized primary standards: AMCO-AEPA-1
(available through Hanna) and formazine.
LP 2000
works with both
solutions.
AMCO-AEPA-1 has a much longer shelf life at all concentrations
(approximately six months, if free from contamination). In addition,
no special handling or disposal is required and a much higher
stability of suspended particles has been observed.
Formazine is highly toxic and is generated by a known carcinogen,
with poor stability (particles settle quickly). Lower concentrations
change value quickly after dilution.
The consistency of
LP 2000
readings by using both standards has
been separately established by Advanced Polymer Systems and
Hanna Instruments. Additional documentation about the formazine
standard and other calibration procedures is available upon request.
VIEWING THE CALIBRATION DATE
•
Turn the meter on and wait for the
display to show "----".
•
Press and hold the DATE/ key. The month and day of last
calibration ("MM.DD") appear while the key is held down.
Note:
The displayed date is the date that was input by the user at
the beginning of the last calibration.
