Owner manual

3 Installation
746 VA Trace Analyzer / 747 VA Stand
3-30
3.6.2 Startup procedure
The reference electrode 4343 is supplied in modular form as the reference system
122122 and the electrolyte vessel 123123 and has first to be filled and assembled as fol-
lows:
1
Add internal electrolyte
Filling of the reference system is necessary only when the optional
6.0728.010 Reference system supplied dry is used, if the internal electrolyte
solution has to be renewed or if the electrical connection is interrupted by
gas bubbles.
Hold reference system 122122 so that diaphragm 129129 faces upwards.
Unscrew diaphragm support 128128.
Fill electrolyte compartment 127127 completely with the desired internal
electrolyte. Expel any air bubbles by tapping shaft gently.
Screw diaphragm support 128128 back on, the electrolyte solution thus
displaced is expelled through the vent opening 125125.
2
Add bridge electrolyte
Fill internal compartment 131131 of the electrolyte vessel 123123 with a suitable
bridge electrolyte whose composition depends on the analyses to be
performed (aqueous or non-aqueous solution, composition of the sup-
porting electrolyte, etc.).
If you use the same solution for the bridge electrolyte and the internal
electrolyte (single-junction operation), the inner diaphragm 129129 can
be omitted to reduce the electrical resistance: Unscrew diaphragm
support 128128 with diaphragm 129129 from the reference system 122122.
3
Screw reference electrode together
Insert the filled reference system 122122 in the vessel 123123 filled with bridge
electrolyte and screw tight. The electrolyte solution thus displaced is ex-
pelled through the vent opening 130130.
4
Install reference electrode in 747 VA Stand and connect
Insert reference electrode 4343 in opening 7979 of the measuring head 4141
(see Fig. 9).
Attach electrode cable 4848 (RE) to reference electrode 4343:
push cable lug under the screw and then tighten screw firmly.
Turn reference electrode 4343 so that the electrode cable 4848 points to the
rear and not to the side (in the latter position it may become kinked and
damaged when cover 2424 is closed).
Wait approx. 20 min before first measurement (it takes some time for a
new reference electrode to become wet).