Lovibond PoolDirect, Instruction And Operation Manual, Page: 34 / 78

34 PoolDirect 9in1_4i 11/2015
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. If there is no defined vial for the blank, the zeroing and the 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 mark
on the vial aligned with the mark on the instrument.
5. Always perform zeroing and test with closed vial cap. Only use cap with sealing ring.
6. Bubbles on the inside of the vial may also lead to errors. To prevent this, remove the
bubbles by swirling the vial before performing the test.
7. Avoid spillage of water in the sample chamber. If water should leak into the instrument
housing, it can destroy electronic components and cause corrosion.
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.
Correct position of the vial (ø 24 mm):
Correct filing of the vial: