VWR International VWR 10 Instruction Manual page 22

Conversion to volume must take into account the density of the liquid as well as evaporation during
the cycle time. For each measurement, the corresponding volume (Vi) can be calculated as follows:
For volumes greater than 20 μL, the evaporation factor can be disregarded.
Maintenance operations
(Disassembly of VWR Electronic Pipette to change and clean parts)
It is best to inspect your pipette regularly and to routinely clean and change parts as required. To
help you to keep up a regular schedule and in the interests of GLP, you can configure your pipette
to display an alarm before servicing is due (refer to Service settings).
The following maintenance operations should only be done when the
pipette is in DISASSEMBLY Mode!
Maintenance warning
VWR Electronic Pipette notifies you, when maintenance is due
(Service alert is set by default to "On"). The following message (1)
will appear: after validation by a click, the following message (2)
appears: If you click to confirm within 10 sec. the pipette will
automatically switch to "disassembly" mode so you can carry
out your maintenance safely. Wait longer than 10 seconds
and the option to have a reminder in one week will appear (3).
Click to confirm. Your pipette will be operational again.
Maintenance operation for single channel models
 Tip-Holder and tip-ejector
These parts must be changed if they are damaged. You may also remove these parts for cleaning
or decontamination purposes.
 Changing the tip-ejector
1/ Keep the tip-ejector button depressed and grip the top of the tip-ejector
with the other hand.
2/ Gently rotate the tip-ejector counter clockwise and separate its
connector from the operating rod.
3/ Pull the tip-ejector away from the body of the pipette.
4/ Clean or autoclave the tip-ejector and refit or replace it by reversing
Wi is the weight as read on the balance
e is the mean evaporation loss during the cycle time
Z expressed inL/mg, is a conversion factor incorporating density of water buoyed in air, at test
temperature and barometric pressure (see Appendix II)
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