Checking The Volume (Calibration) - BRAND Titrette 4760141 Mode D'emploi

The maximum error for a single measurement can be approximated from the sum of error limits EL = A
+ 2 × CV. For the 25 ml instrument this amounts to a maximum of ± 30 µl, and ± 50 µl for the 50 ml in-
strument.
As a result, Class A glass burettes are within the error limits according to DIN EN ISO 385.

10 Checking the Volume (Calibration)

Depending on use, we recommend that gravimetric testing of the instrument be carried out every 3-12
months. For calibration, set the 10 ml instrument to 3 decimal places (page 21). This time frame
should be adjusted to correspond with individual requirements. The complete testing procedure
(SOP) can be downloaded at www.brand.de. You can also carry out a functional test at more frequent
intervals, e.g., by titrating against a standard solution. For GLP- and ISO-compliant evaluations and
documentation, we recommend the EASYCAL™ calibration software from BRAND. A demo version can
be downloaded from www.brand.de.
Gravimetric volume testing according to DIN EN ISO 8655- 6 (for measurement conditions, see Error
limits, p. 58) is performed as follows:
1. Prepare the instrument
Clean the instrument (Cleaning), fill it with distilled Water and then prime it carefully.
2. Check the volume
a.
Dispense 5 drops in a separate vessel and wipe off the titration tube tip.
b.
Press the CLEAR button to set the display value to zero.
c.
10 dispensing operations in 3 volume ranges (100 %, 50 %, 10 %) are recommended.
d.
Turn the hand wheels with both hands without stopping until the test volume is shown on the
display. Wipe off the tip of titration tube.
e.
Weigh the dispensed quantity on an analytical balance. (Please refer to the user manual of the
scale manufacturer.)
f.
Calculate the dispensed volume. The Z factor takes account of the temperature and air buoy-
ancy.
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NOTICE
10 Checking the Volume (Calibration)
Operating manual
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