Guidelines For Photometric Measurements - Orbeco SC450 Manual Del Usuario

Methods
0.0.0
Zero
Test
R ANGE
RESULT
Zero
Test
Zero
Test

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
a 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 to remove fingerprints or other marks
5. Avoid spillage of water or reagent solution into the sample chamber because this can
lead to incorrect test results.
6. Contamination of the transparent cell chamber can result in incorrect readings. Check
at regular intervals and – if necessary – clean the transparent cell chamber using a moist
cloth or cotton swab.
7. Large temperature differences between the instrument and the environment can lead to
errors – e.g. due to the formation of condensation in the cell chamber or on the vial.
8. To avoid errors caused by stray light do not use the instrument in bright sunlight.
SC450_V1_12/2010
The display shows the following:
After zeroing remove the vial from the adapter.
Place the sample in the adapter (Note 2 – 4) making sure that the
marks are aligned.
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 [ZERO/TEST] key for 2 seconds.
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