11
2
Maintenance and care of the titration unit
To retain the function of the titration unit the following
inspection and maintenance work are to be carried out.
Maintenance intervals
Normal operation:
Ü
As a rule, the max. intervals for carrying out all maintenance work are 3 months.
In the case of special load:
Special load is present if, for instance, solutions are used which are suitable to attack glass, e.g. solutions
containing alkali, fluoride or phosphate, or if the average use exceeds 40 titrations per day.
Ü
Once per month, the dosing unit has to be inspected visually in order to check damages, and in addition
a test according to DIN 12 650, Part 6 or Part 7, or ISO DIS 8655, Part 3, has to be carried out.
Ü
Once per quarter the electrical contacts (plugs, stirrer, manual key button) have to be inspected for cor-
rosion, if the titration unit is used in premises with an occasional occurrence of corrosive matters in their
atmosphere.
Ü
If there is suspicion that a solution is attacking the glass excessively, the maintenance intervals are to be
reduced accordingly.
In case of disturbances:
Ü
If a disturbance, a malfunction or another defect becomes obvious, the maintenance work has to be car-
ried out immediately.
Ü
If it has to be assumed that
!
safe operation is no longer possible
!
, please refer to chapter 1
„Warning and safety information“.
Maintenance work to be carried out
Ü
Check whether humidity has penetrated below the dosing unit. To do so remove the dosing unit (chapter
3, Fig. 1 to 4 resp. Fig. 7 to 10). If humidity can actually be found there, one can conclude that the piston
in the cylinder is no longer tight.
Ü
Check the hoses, the threaded connections and the seals for visible damage, contamination and leak-
age. Installation of the screw connections
&
Fig. 11.
Ü
Check the electrical plug-in contacts for corrosion and mechanical damage.
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Defective parts have to be repaired or replaced by new parts. Defective glass parts have to be replaced
in any case.
After each maintenance process the measurement-technical reliability according to DIN 12 650, Part 6 or
Part 7, or ISO DIS 8 655, Part 3, has to be verified.
The measurement-technical reliability - including maintenance - is offered by SCHOTT-GERÄTE upon re-
quest (including manufacturer’s certificate, if requested). For this purpose the titration unit has to be sent to
SCHOTT-GERÄTE.
Use interruptions
Ü
If the titration unit is not being used over a longer period of time, the liquids contained in the system have
to be removed, and the titration unit has to be flushed out with distilled water. If the liquid is left in the
system, one has to reckon with corrosion and an alteration of solutions used over the time. Since the
state of the art does not provide plastic hoses which are absolutely free of diffusion occurrences, these
precaution measures apply in particular to the hose-line section.
Cleaning
Ü
The titration unit can be cleaned using a moist piece of cloth with normal household cleaning agents.
Ü
The bottom and rear side have to be treated dry. In no case must liquid penetrate into the interior of the
titration unit.
