VWR 2 Manual De Instrucciones página 8

• Eject the tip by pressing the tip ejector button, Fig. 3F.
It is only necessary to change the tip if a different liquid is
being sampled or if the volume setting is changed.
Filters
A replaceable filter installed in a seat in the bottom part
of the shaft is used in 5000 μl and 10000 μl pipettors
(Fig. 2L). The filter prevents the aspirated liquid from
entering into the shaft and thus from polluting the inside
of the shaft and the piston. Using the filter is especially
important when aspirating and dispensing large volumes
of liquid.
VWR pipettor tips
VWR tips are made from high performance polypropylene
and their quality guarantees the precision and accuracy
associated with the pipettor.
Strict control is maintained throughout the manufacturing
process to ensure the highest quality.
The accuracy and precision figures for the VWR
Pipettor are only guaranteed when VWR tips are used.
The use of inferior quality tips will seriously degrade the
performance of the pipettor.
Tips 10
These tips are used for volumes between 0.1 μl and 10 μl.
They are used with the VWR2 and the VWR10 models.
Tips 200
These tips are used for volumes between 2 μl and 200 μl.
They are used with the VWR20, VWR100, VWR200 models.
Tips 1000
These tips are used for volumes between
100 μl and 1000 μl.
They are used with the VWR1000 model.
Tips 5000
These tips are used for volumes between
500 μl and 5000 μl.
They are used with the VWR5000 model.
Tips 10000
These tips are used for volumes between
1000 μl and 10000 μl.
They are used with the VWR10000 model.
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Recommendations
The recommendations below will ensure maximum accu-
racy and precision from the pipettor.
• Make sure to operate the pipettor slowly and smoothly.
• The depth of immersion in the sample liquid should be
the minimum necessary and should remain constant
during aspiration.
• The pipettor should be held in a vertical position.
• Change the tip when volume setting is changed or
when a different liquid is to be aspirated.
• Change the tip if a droplet remains on the end of the tip
from the previous pipetting operation.
• Each new tip should be pre-rinsed with the liquid to be
pipetted.
• Liquid should never enter the pipettor shaft. To prevent
this:
- Press and release the pushbutton slowly and smoothly
- Never turn the pipettor upside down
- Never lay the pipettor on its side when there is liquid
in the tip.
• Never force the volumeter beyond its recommended
limits.
• When pipetting liquids with temperatures different from
the ambient temperature, it is recommended to pre-
rinse the tip several times before use.
• Do not pipet liquids with temperatures above 70°C.
• When pipetting acids or corrosive solutions which emit
vapors, it is recommended to disassemble the shaft
and to rinse the piston and seal with distilled water after
finishing the pipetting operation.
Recalibration
The pipettor is calibrated by gravimetric method, using
VWR tips and distilled water, at the temperature 20±1°C,
based on EN ISO 8655 standard.
If during pipettor operation you find that the accuracy
error (the difference between the real aspirated volume
and the preset volume) exceeds the permissible value
given in the table on the page 11, the pipettor recalibra-
tion procedure should be carried out.
Before starting the recalibration it is necessary to check
whether the following requirements have been fulfilled
during error determination:
Version: 1
Issued 17/03/2014
ENGLISH
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