BRAND PLT Mode D'emploi page 58

5 Performing the test
5 Performing the test
5.1 Test preparation
Before the test, you must decide whether a dynamic or static test is to be performed.
Dynamic or static test?
Dynamic test
Static test
Test with or without pipette tip?
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Operating manual
With the dynamic test, you can not only detect static leaks
but also determine whether a defective (contaminated,
scratched) piston is the cause of a leak.
Over the course of the measurement, you should press the
plunger button down completely and evenly 2–3 times. The
associated piston movement allows piston faults to be rec-
ognized.
For 5 mL and 10 mL pipettes, the button should be pressed
and released relatively slowly.
In the dynamic testing of electronic pipettes, the piston
should be in the uppermost position at the beginning and
should be brought back to that position before the end.
In the static test, in contrast, the plunger button is not
pressed, i.e., the piston is not moved, during the test.
In electronic pipettes, the piston can be positioned in the up-
permost position or at the first
Leaks occurring during the piston stroke thus cannot be
identified in this case.
We recommend that the dynamic test be performed.
The test can be performed with or without the pipette tip.
We recommend that the test be performed with a mounted
unused tip so that the entire pipette system is tested.
If a leak is identified, you can repeat the test without a tip to
determine whether the leak arises from the tip cone/tip cou-
pling region. To perform the test without a tip, you must first
change the adapter; see Changing the adapter and fil-
ter, p. 60.
Hold the pipette firmly during the test.
PLT unit 997960