Lovibond CheckitDirect Mode D'emploi page 13

Method
GB
Zero
Test
RANGE
RESULT
Zero
Test
Mode
Guidelines for photometric measurements
1. Run samples and blanks with the same batch of vials.
The blank is stable when stored in the dark and can be used for further measurements
with vials from the same batch.
2. Don't place hot vials in the adapter. Allow the vials to cool to room temperature for
minimum 45 minutes. It is recommended to leave the vials to cool over night.
3. Suspended solids in the vial lead to incorrect measurements. For this reason it is important
to place the vials carefully in the adapter. The precipitant at the bottom of the sample
should not be suspended.
4. Clean the outside of the vials with a towel. Finger-prints or other marks will be removed
5. Avoid spillage of water or reagent solution into the sample chamber because this can
lead to incorrect test results.
6. Contamination of the optics (LED and photo-sensor) in the sample chamber will result in
incorrect measurements.
The windows of the sample chamber must be checked at regular intervals and cleaned as
necessary. Use a moistened cloth and cotton buds for cleaning purposes.
7. Large temperature differences between the photometer and ambient conditions can lead
to incorrect measurements, or build-up of condensate around the optics of the vial.
8. To avoid errors caused by stray light do not use the instrument in bright sunlight.
CheckitDirect COD_3b 05/2011
Press the [ZERO/TEST] key.
The "Range" symbol flashes for approx. 3 seconds.
The result appears in the display.
LR-/MR-range: in mg/l
HR-range: in g/l
The result is saved automatically.
Tolerance:
± 3.5 % (full scale)
Repeating the test:
Press the [ZERO/TEST] key again.
New zero calibration:
Press the [MODE] key until the desired range symbol appears in the
display again.
.
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