General notes
GB
Guidelines for photometric measurements
1 .
Vials, caps and stirring rods should be cleaned thoroughly after each analysis to prevent
interferences . Even minor reagent residues can cause errors in the test result .
2 .
The outside of the vial must be clean and dry before starting the analysis . Clean the
outside of the vials with a towel . Fingerprints or other marks will be removed .
3 .
Zero calibration and test must be carried out with the same vial as there may be slight
differences in optical performance between vials .
4 .
The vials must be positioned in the sample chamber for zeroing and test with the
on the vial aligned with the
5 .
Always perform zeroing and test with the vial cap tightly closed . Only use the cap with
a sealing ring .
6 .
Bubbles on the inside wall of the vial leads to incorrect measurements . To prevent this,
remove the bubbles by swirling the vial before performing the test .
7 .
Avoid spilage of water into the sample chamber because this can lead to incorrect test
results .
8 .
Contamination of the lens in the sample chamber can result in errors . Check at regular
intervals and – if necessary – clean the light entry surfaces of the sample chamber using
a moist cloth or cotton buds .
9 .
Large temperature differences between the instrument and the environment can lead to
errors – e .g . due to the formation of condensation in the area of the lens or on the
vial .
10 .
To avoid errors caused by stray light do not use the instrument in bright sunlight .
11 .
The reagents must be added in the correct sequence .
Method notes
•
Prior to measurement ensure that the sample is suitable for analysis (no major interferences)
and does not require any preparation i .e . pH adjustment, filtration etc .
•
Reagents are designed for use in chemical analysis only and should be kept well out of
the reach of children .
•
Ensure proper disposal of reagent solutions .
•
Material Safety Data Sheets: available on request
(Internet: www .tintometer .de)
18
mark on the instrument .
mark
MiniDirect_Cl_1 09/2008