Metrohm 746 VA Trace Analyzer - Manual (Page 34)

3.3 Installation of 747 VA Stand
746 VA Trace Analyzer / 747 VA Stand
3-7
3 Attachment of a 747 VA Stand for the 695 Autosampler
• Switch off 746 VA Trace Analyzer using the mains switch 11 11.
• Plug one end of the third 6.2135.000 EBUS cable into connector of the
second EBUS cable and fasten together by tightening the screws in the
cable connector.
• Plug the other end of the third EBUS cable into connection 34 34 of the third
747 VA Stand and fasten to the instrument by tightening the screws in the
cable connector.
• Using a screwdriver, set stand address 35 35 of the 747 VA Stand to "3"
(arrow must point to the number "3").
3.3.2 Equipping the measuring head
The fixtures inserted in the openings and connections of the measuring head 41 41 in
the 747 VA Stand depend on the working electrode selected (MME or DME) (see
Fig. 9). The fully equipped measuring head for operation with a multi-mode elec-
trode is illustrated in section 2 (Figs 7 and 8), that for operation with a rotating disk
electrode in section 3.5 (Fig. 16).
When equipping the measuring head for the first time, the best procedure is as fol-
lows:
1 Preparations
• Prepare multi-mode electrode MME 38 38 (details, see section 3.4) or rotat-
ing disk electrode RDE (details, see section 3.5) for operation.
• Prepare reference electrode 43 43 (details, see section 3.6) for operation.
• Tilt back cover 24 24 of measuring head arm.
2 Insert dummy stoppers
without automatic rinsing:
• Screw dummy stopper 62 62 (6.1446.040) into opening 73 73.
• Screw dummy stopper 61 61 (6.1446.040) into opening 74 74.
with and without automatic rinsing:
• Screw dummy stopper 42 42 (6.1446.040) into opening 78 78.
• Insert 6.2730.030 Stopper into enclosed nipple 44 44 and push enclosed
O-ring over the stopper.
• Screw nipple 44 44 with stopper into opening 80 80 by hand.
3 Insert 4-way microtip
• Remove stopper from nipple 44 44 and insert 4-way microtip 47 47 into nipple
44 44 as far as it will go.
• Tighten nipple 44 44 using a 6.2739.010 Wrench until the 4-way microtip 47 47
can no longer move.
• Pull the 4 lengths of PTFE tubing of the 4-way microtip 47 47 in succession
from above through the opening 86 86 (connection of 685 Dosimat, see
section 3.9; connection of 700 Dosino, see section 3.10).