Recalibration - HTL discovery comfort DV8-10 Handbuch

• The DISCOVERY Comfort 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 DISCOVERY Comfort
shaft. To prevent this:
- Press and release the pushbutton slowly and smoothly.
- Never turn the pipette upside down.
- Never lay the pipette on its side when there is liquid in
the tip.
• Never force the volume setting beyond its recommend-
ed 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 pipette liquids with temperatures above 70°C.
• When pipetting acids or corrosive solutions which emit
vapours, it is recommended to disassemble the shaft
and to rinse the piston and seal with distilled water after
finishing the pipetting operation.

8 - RECALIBRATION

HTL pipettes are calibrated by gravimetric method, using
HTL tips and distilled water, at the temperature 20±1°C,
according to EN ISO 8655 standard.
If during pipette 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 in section 1, the pipette recalibration
procedure should be carried out.
Before starting the recalibration it is necessary to check
whether the following requirements have been fulfilled
during error determination:
• the ambient temperature, and the temperature of the
pipette, tips and water was identical
• the density of the liquid used is close to that of distilled
water
• a balance with appropriate sensitivity has been used.
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Volume checked [μl]
0.1 - 10
10 - 100
> 100
• mg/μl conversion factor has been taken into account
• the requirements given in sections 3 and 7 have been
fulfilled
If the above conditions are satisfied and the accuracy
error for selected volume given in section 1 exceeds the
permissible value, the pipette recalibration procedure
should be carried out.
The recalibration can be performed within one full
turn of the key to the right or to the left only.
Recalibration conditions:
• Ambient temperature and the temperature of the pipet-
te, tips and liquid should be within the range 20-25°C
and stabilised during weighing within ±0.5°C
• Measurements should be conducted using distilled
water
• Balance sensitivity should be suitable for the volume to
be controlled
Recalibration procedure:
• Set the dose volume depending on the pipette volume
according to the following table:
Range
Preset
of the pipette
Model volume
volumes
[μl]
DV2, D2 0.1 - 2
DV10, D10 0.5 - 10
DV20, D20 2 - 20
DV50, D50 5 - 50
DV100, D100 10 - 100
DV200, D200 20 - 200
DV250, D250 50 - 250
DV1000, D1000 100 - 1000
DV5000, D5000 1000 - 5000
DV10000, D10000 1000 - 10000
• Perform 5 aspirations, weigh each one and calculate
the average value of the aspirations
ENGLISH
Balance sensitivity [mg]
≤ 0.001
≤ 0.01
≤ 0.1
Volume change
Permissible ΔV for full turn
volumes of the calibration
[μl] [μl] key [μl]
(24 increments)
0.2 0.176 - 0.224 0.06
0.5 0.48 - 0.52 0.33
2 1.94 - 2.06 0.63
5 4.875 - 5.125 2.50
10 9.84 - 10.16 2.50
20 19.76 - 20.24 6.30
50 49.5 - 50.5 6.30
100 98.4 - 101.6 25.00
1000 994 - 1006 125.00
1000 975 - 1025 250.00
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