Maintenance - Thermo Scientific Finnpipette Novus 46200000 Guide D'utilisation

Formulas for calculating results
Conversion of mass to volume
V = (w + e) x Z V = volume (μl)
w = weight (mg)
e = evaporation loss (mg)
Z = conversion factor for μl/mg conversion
Evaporation loss can be signifi cant with low volumes. To determine mass loss, dispense water to
the weighing vessel, note the reading and start a stopwatch. See how much the reading decreases
during 30 seconds (e.g. 6mg = 0.2mg/s).
Compare this to the pipetting time from tareing to reading. Typically pipetting time might be 10
seconds and the mass loss is 2 mg (10s x 0.2mg/s) in this example. If an evaporation trap or lid on
the vessel is used the correction of evaporation is usually unnecessary.
The factor Z is for converting the weight of the water to volume at test temperature and pressure.
A typical value is 1.0032μl/mg at 22°C and 95 kPa. See the conversion table on page 96.
Inaccuracy (systematic error)
Inaccuracy is the difference between the dispensed volume and the selected volume of a pipette.
A = V - V A = inaccuracy
0
V = mean volume
V = nominal volume
0
Inaccuracy can be expressed as a relative value: A% = 100% x A / V
Imprecision (random error)
Imprecision refers to the repeatability of the pipettings. It is expressed as standard deviation (s)
or coeffi cient of variation (cv)
Standard deviation can be expressed as a relative value (CV) CV = 100% x S / V
When the Finnpipette Novus is not in use, make sure it is stored in an upright
position. We recommend a Finnpipette stand for this purpose.
The part # refer to exploded views beginning at page 101.
Daily checking
The pipette should be checked at the beginning of each day for dust and dirt on
the outside surfaces of the pipette. Particular attention should be paid to the tip
cone. No other solvents except 70 % ethanol should be used to clean the pipette.
Short-term service
If the pipette is used daily it should be checked and lubricated every three months.
The servicing procedure starts with choosing the Service-mode from the menu
(Menu -> Options -> Service).
Pipettes up to 1000 μl
1. Remove the lower tip ejector sleeve 13 by pulling it
out (snap fi tting).
2. Push down the ejector button and take the upper ejector
top 11 between fi ngers.
3. Release the ejector button to up position, but hold the
tip ejector top 11 in down position with the fi ngers.
4. Remove the tip cone by pulling it out (snap fi tting).
5. Press and hold the trigger down to drive out the piston.
6. Insert the special piston removal tool and pull out
the piston 14. The number 2 end is for 300μl and
1000μl pistons, the number 1 end for all the smaller
volumes. See picture. Release the trigger.
7. Check the tip cone for foreign particles.
s = standards deviation
V = mean volume
n = number of measurements

Maintenance

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