BRAND Transferpettor micro Instrucciones De Manejo página 46

7 Checking the volume
7 Checking the volume
We recommend testing the instrument every 3 to 12 months depending
on the level of use. However, the testing cycle can be adapted to meet in-
dividual requirements. For gravimetric volume testing, we recommend
the test procedure as described (e.g., in DIN EN ISO 8655 Part 6).
1. Setting the nominal volume
a. Set the maximum specified instrument volume (for procedure, see ).
2. Conditioning the pipette
a. Condition pipette before testing by pipetting once with test liquid
(distilled water).
3. Performing the test
a. Aspirate the test liquid and pipette into the weighing vessel.
b. Weigh the pipetted amount with an analysis scale. (refer to the oper-
ating manual of the balance manufacturer.)
c. Calculate the pipetted volume. In doing so, take into account the tem-
perature of the test liquid.
d. At least 10 pipettings and weighings are recommended. With a digital
pipette, perform at least 10 weighings in three volume ranges (100%,
50%, 20%).
Calculation (for nominal volume)
x = weighing results
i
Z = Correction factor (e.g. 1.0029 µl/mg at 20°C, 1013 hPA
Operating manual
46
n = number of weighings V = nominal volume
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