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9.1. Testing the Performance
It is recommended to check the performance of your electronic pipettes regularly
(e.g. every 3 months) and alwayys after in-house maintenance. However, users
should establish a regular testing routine for their pipettes depending upon the
accuracy requirements of the application, frequency of use, number of operators
using the pipette, nature of the liquid dispensed and the acceptable maximum
permissable errors establishes by the user. (ISO 8655-1).
Performance test should take place in a draught-free room at 15-30°C, constant
to ±0.5°C and relative humidity above 50%. The pipette, tips and the test water
should have stood in the test room a suf
fi
cient time (at least 2 hours) to reach the
equilibrium with the room conditions. Use distilled or deionised water (grade 3)
and analytical balance with a readability of 0.01 mgs. (ISO 8655-6).
1. Carefully
fi
t the tip onto the tip cone.
2. Prewet the tip with test water by pipetting the selected volume 5 times.
3. Replace the tip and prewet the new tip once.
4. Aspirate the test water, immersing the tip only 2-3 mm below the surface
of the water and keeping the pipette vertical. Withdraw the pipette
vertically and touch the tip against the side wall of the container.
5. Pipette the water into the weighing vessel, touching the tip against the
inside wall just above the liquid surface at an angle of 30°-45°. Withdraw
the pipette by drawing the tip 8-10 mm along the inner wall. Read the
weight in mgs.
6. Repeat ten times and record each result.
7. Convert the recorded masses to volumes by multiplying the mass with
the correction factor Z (at 22°C and 101.3 kPa: Z=1.0033).
Note:
Users should establish their own perfomance speci
fi
cations based
on the
fi
eld of use and the accuracy, requirements set on the pipette (ISO
8655-1). This method is based on ISO 8655.
10. MAINTENANCE
Biohit Proline Electronic pipettes require regular cleaning to ensure trouble-
free operation. To clean and decontaminate the pipette lightly spray the
outside of the pipette with Biohit Proline Biocontrol (cat.no. 724004, 5l) or
ethanol. Wipe dry with a soft cloth. DO NOT AUTOCLAVE. Change the tip
cone
fi
lter regularly.
Note:
The pipette must be turned off prior to servicing!
