Eppendorf Research pro - Manual (Page 25)

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The Research pro must be calibrated only for solutions with a density, viscosity, surface tension
and vapor pressure that are greatly different to that of water. If the density of an aqueous
solution changes (e.g. due to a different salt concentration) by roughly ± 10 %, the volume
changes by approximately ± 0.2 %. This does not apply when other relevant sizes change as
well.
The actual volume can be checked via weighing (see Sec. 2, "Technical data"):
If the volume selected (display volume) is the same as the actual volume, no correction is
necessary.
If there is a significant difference between the actual volume and the display volume, the
following points must be answered "Yes" before calibration is modified:
• the pipette is leaktight. The aspirated liquid does not drip straight out of the pipette following
aspiration.
• there is no difference in temperature between the pipette and the solution.
• the optimum pipetting option was selected for the liquid.
• the precision scale has not been subjected to shocks, draughts etc..
• the correct numerical value for "dense liquid at weighing temperature" was selected for the
calculation according to (1).
• the check was made with epT.I.P.S. and the correct size of epT.I.P.S.
(see Sec. 2 "Technical data").
If the place where the pipette is used is at extremely high altitude, an adjustment must be made
in line with the ambient air pressure. At 1,000 m above sea level, there is a volume error of
approx. –0.4 %
The internal volume correction of the Research pro uses the following formula:
Actual volume = m • "Stroke movement" + b (2)
"m" is the definition of the gradient and "b" is the definition of the axis section of this equation
(2).
When the device is delivered, m = 1,000 and b = 0.0 µL. If this data is changed, the CAL symbol
appears in the bottom right of the display. If the device is reset to the original values, the CAL
symbol disappears.
If the CAL symbol appears in the display, the "stroke movement" which is selected or
displayed is converted by the pipette using the user-defined "m" and/or "b" in order to ensure
that the actual volume of the liquid used corresponds to the display volume.
It is essential to inform all users of the changes made to the calibration data! We
recommend labeling the pipette as follows (example only):
Pipette calibrated only for use of "xy" with option "ZZZ".
Type of ep Dualfilter T.I.P.S.
10 µL
20 µL
100 µL
300 µL
1000 µL
5000 µL
Volume restriction for RP and DIS
9 µL
17 µL
100 µL
280 µL
970 µL
4700 µL
5.11.1 Changing the calibration (CAL)
Mean value of weighings
Density of liquid at weighing temperature
Actual volume = (1)
Operation
5 Operation
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E05_2 Bedienung A5 Seite 25 Dienstag, 9. Februar 2010 5:53 17