6
Test room
The calibration should be performed in a draught-free room with constant temperature and
The test pipette and the test liquid must be at equilibrium with the room temperature. For this,
Temperature
humidity.
leave the pipette (without the packaging) and the test liquid for at least 2 hours in the test room.
Try to avoid temperature changes (e.g.from sun radiation). Then carry out a comparison of the
temperature from pipette, liquid and room.
Test liquid
Distilled or deionised water of a minimum quality 3 according to ISO 3969. The maximum difference
of room and water temperature should be 0.5 °C.
Thermometer
Use only thermometers with a maximum measurement error of 0.2 °C.
Hygrometer
Considering the measuring tolerance of the hygrometer a relative atmospheric humidity of 40
- 60% should be reached.
Balance
Recommended specifications, see table:
Selected volume* of the
device to be tested
Resolution of the
Balance display
Repeatability
and linearity
1 µl
< V
≤
10 µl
0.001
V
mg
Standard
uncertainty
mg
µl
0.002
0.002
10 µl < V
≤
100 µl
0.01
0.02
0.02
100 µl <
V
≤
1000 µl
0.1
0.2
0.2
1 ml < V
≤
10 ml
0.1
0.2
0.2
*For practical purposes, the nominal volume may be used to choose the balance.
Recipient vessel
Vessel (e.g. Erlenmeyer flask) filled with test liquid. Prevent a cooling of the water in the recipient
vessel through evaporation.
Weighing vessel
Vessel (e.g. Erlenmeyer flask) filled with water to a level that the bottom is completely covered.
Provide an evaporation protection for testing volumes
< 100 µl.
3. Test instruments and environment
