Metrohm 797 VA Computrace - Manual (Page 35)

2.3 Multi-Mode Electrode (MME)
797 VA Computrace / Hardware-Manual 8.797.8001EN
27
94 Filling cone (4.420.2860)
(part of the filling tubing 93)
95 Gas wash bottle
96 Tubing coupling (6.1809.000)
(part of the filling tubing 93)
5 Evacuating in vertical position
• Place Multi-Mode Electrode 21 vertically in the electrode holder 92 (see
Fig. 11-1).
• Evacuate for ca. 2 min in this position.
6 Evacuating in inclined position
• Carefully tilt Multi-Mode Electrode 21 in the electrode holder 92 to an in-
clined position and continue evacuating (see Fig. 11-2).
7 Release vacuum
• As soon as mercury issues from the tip of the glass capillary 87 into the
filling tubing 93, carefully release the vacuum by opening the vacuum re-
lease tap.
The filling tubing 93 must not be disconnected from the glass capilla-
ry 87 when under vacuum, otherwise the mercury which has issued
from the capillary would be sprayed onto the tubing wall and can no
longer be disposed of in drop form!
• Tap the glass capillary 87 gently by hand so that any mercury drops at its
tip are knocked into the filling tubing 93.
• Disconnect filling tubing 94 with filling cone from glass capillary.
• Place Multi-Mode Electrode 21 in a horizontal position in the electrode
holder 92 (see Fig. 11-3).
From now on, the MME must be left in this position until it is installed
in the stand!
8 Install Multi-Mode Electrode in 797 VA Computrace Stand
• With measuring head arm 23 tilted back, push empty measuring vessel 7
into the holder 5 of the 797 VA Computrace Stand and then lower measur-
ing head arm 23.
• Carefully insert Multi-Mode Electrode 21 in opening 58 of the measuring
head 24 (during insertion, the tip of the capillary 87 must not touch the
measuring head) and push in as far as it will go.