Checking The Volume - Easy 20K+ Manual Del Usuario

4. Rinse the filling valve in the cleaning solution, and clean with soft brush. Should valve ball become
sticky, push it into the filling opening of valve with a pointed instrument, and release it.
5. Screw the cleaned/new filling valve
together with its seal into the valve block and fasten it firmly using the mounting tool.
10. Autoclaving
This instrument withstands steam sterilization at 121 °C, 1 bar absolute (15 psi) for 20 minutes in
accordance with general guidelines. It is the user's responsibility to ensure effective autoclaving.
10.1. Preparation prior to the autoclaving
1. Clean the instrument before sterilization.
2. Remove the filling tube (10) and put it on a towel.
Avoid contact with hot metal surfaces.
3. Lay the dispenser with piston at the bottom extreme position on the towel.
4. Autoclave the dispenser.
Note:
Wait the dispenser to cool down in the closed autoclave to avoid deformation through too rapid
cooling. After every autoclaving, inspect all parts for deformities or damage. If necessary, replace
them. Do not reassemble the instrument until it has cooled down to room temperature (cooling time
approx. 2 hours).
Mounting tool can be steam sterilized at 121 °C.

11. Checking the volume

The accuracy and coefficient of variation of the instrument are determined gravimetrically as follows:
Set to the nominal volume.
-
Dispense distilled H2O.
-
Weigh the dispensed quantity on an analytical balance.
-
Calculate the dispensed volume taking the temperature into account.
-
Perform at least 10 dispensing and weighing operations.
-
Calculate the accuracy (A%) and the coefficient of variation (CV%) by means of the formular
-
used in statistical quality control. The proceeding is described e.g., in DIN EN ISO 8655-6.
Observe the operating manual of the balance manufacturer and the corresponding standards.
Mean value: ��̅ = Σ��̅ /��,
��
= �������������� ���� ��������ℎ��������
��̅
��
�� = ������������ ���� ��������ℎ��������
Mean volume: ��̅ = ��̅ ∙ ��
�� = �������������������� ������������ (��.��.1.0029 ����/���� ���� 20℃,1013ℎ����)
Accuracy: A%=(��̅ −��̅
/��̅
0
= �������������� ������������
��̅
0
Standard deviation: s = Z ∙ √Σ(��̅
Coefficient of variation: CV% = 100/��̅
) ∙ 100,
0
−��̅ )
/��−1
2
��
9