BRAND Transferpette S Instrucciones De Manejo página 49

b. Weigh the pipetted amount with an analysis scale. (Please refer to
the user manual of the scale manufacturer.)
c. Calculate the pipetted volume. In doing so, take into account the
temperature of the test liquid.
d. At least 10 pipetting series and weighings in 3 volume ranges
(100%, 50%, 10%) are recommended.
Calculation (for nominal volume)
x
= Weighing results
I
Correction factor
Z =
(e.g. 1.0029 µl/mg at 20 °C, 1013 hPa)
Mean
Mean volume
Accuracy*
Coefficient of variation*
Standard deviation*
*) = Calculation for accuracy (A%) coefficient of variation (CV%): A%
and CV% are calculated using the formulas of statistical quality control.
Test instructions (SOPs) and a version of the calibration software
EASYCAL™ 4.0 are available for download at www.brand.de.
Transferpette® S 9974 88 V1
n
Number of weighings
=
∑
x
x –
I
=
n
—
.
x –
Z
V
=
—
V
V
–
A% =
V
0
V
Nominal volume
0 =
100 s
CV%
=
—
V
.
Z
s
=
NOTICE
6 Checking the volume
0
.
100
x –
∑
2
)
(
–
x
I
– 1
n
Operating manual
47