ABB Nitrate 8236, Инструкция по эксплуатации

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i) Take a washer from the spares pack in the kit and place it over
the membrane, carefully centralising it in the end cap.
j) Fit the end cap assembly onto the body, screwing up tightly.
k) Support the electrode vertically with its end cap lowermost.
Using the 1 ml glass syringe, extract 1.5 ml of ion exchange
liquid from its container and inject it carefully into the body
through the filling hole provided. The electrode must remain in
a near vertical position from now on.
l) Screw the inner electrode down four complete turns and then
a further
1 /
2
turn (±0.1 turn). The tip of the electrode should
now be pressing against the membrane.
m) Blot the membrane with an absorbent tissue to remove
excess exchanger.
n) Push the cap onto the electrode body so that it covers the
filling hole.
Note. The electrode will not show its best performance until it
has been in use in a stirred nitrate solution, in the monitor for
2 to 3 hours. Response and stability improves over a 3 day
period following assembly.
o) Ensure that the ion exchange liquid and membranes are at
room temperature before use.
p) Ensure that the protective cap is refitted to the plastic syringe
to preserve its contents. Rinse the plastic tube with distilled
water.
q) Store the electrode in a standard nitrate solution (e.g. 10 mg l -1 )
when not in use.
r) Rinse syringes, etc., in methanol and allowed to air-dry.
Warning. Methanol is highly flammable. Avoid contact with
skin and eyes. Do not inhale the vapour.
s) The ion exchange liquid level will require topping up
periodically. The level must be maintained at least 5 mm
above the body seal 'O' ring.
Fitting the Electrodes
When the Nitrate Electrode has been prepared for use in
accordance with the assembly procedure, fit it and the Reference
Electrode as follows:
a) Fit the Nitrate Electrode into the plastic holder supplied, slide
the retaining 'O' ring over the end of the electrode body and
insert it into the sloping aperture of the flowcell. Screw down to
compress the 'O' ring.
b) Connect the electrode lead into the co-axial socket above the
flowcell on the right hand side.
8.2.6 Consumables Spares Kit
If one is not supplied, it should be ordered before the end of the
first year of operation. This kit includes all the components which
are recommended for replacement annually (see Section 10).
This annual refurbishment ensures a high level of reliability from
the monitor over a period of many years. Another kit should be
ordered when this one is used so that all the items are available
throughout the following year's operation. The consumable
spares kit is in addition to the electrode spares kit.
The kit contains the following:
• one set of pump tubing
• one set of pump capstans
• a complete set of plumbing tubing
• sundry items – 'O' rings, tube connectors, pump tube
bungs and fuses
• plastic syringe and bottle brush – for cleaning pipework,
valves, flowcell and constant-head unit.
8.2.7 Fitting the Electrode
Assembly
The monitor is supplied with an electrode body, an inner electrode
and a refurbishing kit. These must be assembled as follows:
a) Unpack the inner electrode. Remove the protective teat and
place the electrode horizontally on the bench.
b) Remove the protective cap from the plastic syringe containing
gelled filling solution in the refurbishing kit and fit the plastic
tube, supplied in the kit, to the nozzle.
c) Insert the free end of the tube into the cavity housing the
chloridised silver wire element at the tip of the electrode. Take
care not to damage the chloridised silver wire, but make sure
that the tube reaches the end of the cavity.
d) Holding the inner electrode steady, slowly inject the gel into
the cavity, gradually withdrawing the tube as the gel is
injected. Finish with a slightly convex gel surface at the orifice.
e) Remove the end cap from the electrode body and insert the
inner electrode, taking care not to touch the gel surface on the
top collar of the body as the electrode is inserted.
f) Hold the electrode vertically and screw the central electrode in
until the end of the glassware is flush with the end face of the
electrode body.
g) Withdraw the electrode four complete turns.
Warning. Wear protective gloves and perform the following
steps under a fume hood. Avoid skin contact with the ion
exchanger solution; if contact occurs, wash off immediately
with soapy water.
h) Using tweezers place the membrane (coloured white) into the
end cap.
…8 MAINTENANCE