Thermolab Sartorius MC210, Руководство пользователя

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factors have different values depending on the module, so please check
that you choose the right module.
5. Enter these factors to the OLD FACTORS fields of the calibration software.
6. To get the new factors, click the CALCULATE button. The new factors will be
displayed.
- Alternatively the Finnpipette Calibration Software may be used to determine the
new HK- and PK-factors.
- Take the pipette again and change the HK- and PK-factors with + and - buttons,
then accept the new values by pushing the SET button.
- After the adjustment, check the calibration as described above. When using the
Finnpipette Calibration Software, continue according to the on-screen menus
after entering the new values for HK- and PK-factors to the handle unit.
Formulas for calculating results
Conversion of mass to volume
V = (w + e) x Z
V = volume (
µ
l)
w = weight (mg)
e = evaporation loss (mg)
Z = conversion factor for mg/
µ
l conversion
Note:
Evaporation loss can be significant with low volumes. To determine mass loss, dis-
pense water into the weighing vessel, note the reading and begin timing with a
stopwatch. Check how much the reading decreases during the 30 seconds. Com-
pare this to the pipetting time. Typically, the pipetting time might be 10 seconds
and the mass loss 2 mg. If an evaporation trap or lid on the vessel is used, an
evaporation correction is unnecessary.
The conversion factor Z is for calculating the density of water suspended in air at
the test temperature and pressure. See the conversion Table 1 on page 23.
Accuracy (systematic error)
Accuracy is the difference between the dispensed volume and the selected
volume of a pipette.
Accuracy is expressed on the calibration certificate as a relative value:
V = volume (
µ
l]
w = weight (mg)
e = evaporation loss (mg)
Z = conversion factor for mg/
µ
l
V = (w + e) x Z
A = accuracy
V = mean volume
V
s
= selected volume
A = V – V
s
ACC% = 100% x
A
V
s