Flowmeter SVTU-11B, Руководство по эксплуатации

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12.4 There are two types of maintenance for meters: #1 and #2.
12.4.1 Maintenance #1 is carried out on a meter operation place once in six months
and includes visual check and check of working capacity.
Check visually:
−
no leak in places of meter installation;
−
reliability of contact joints;
−
no mechanical damages on plastic details;
−
safe isolation of connecting cables;
−
measuring data output in accordance with items 11.2.1.
At the end of the heating season it is recommended to clean of flow sensor surfaces us-
ing washing-up liquids, weak solutions of alkalis or acids (without mechanical cleaning). If
water meter was out of service for a long period of time it is recommended to switch the me-
ter into ‘Stop’ mode and provide the guaranteed absence of the water in a flow measurement
section.
12.4.2 Maintenance #2 is carried out before regular verification of meters.
Following operations should be carried out:
−
operations, provided by maintenance #1;
−
visual check of precipitation on the inner surface of flow measurement section (FS);
−
dismantling and cleaning of FS according to item 12.5.1 and dismantling and clean-
ing of RTD if severe precipitation has been detected.
Dismounting and cleaning of FS of DN20 should be carried out only at manufacturing
company or in authorized labs for verification.
Dismounting and cleaning of FS is carried out in the following way:
−
to dismount ultrasonic flow sensors (except for FS of DN20);
−
to dismount FS from the pipeline (if possible);
−
to carry out visual check of FS and, if necessary, to clean mechanically its inner sur-
face from precipitation;
−
to wash out inner FS surface by a synthetic washing-up liquid of any type and then
by water.
12.5 Meters (calculator, ultrasonic FlS, temperature sensors, flow measurement sections)
undergo a verification after maintenance #2. Recalibration interval is no more than 4 years.
FS of DN20 should undergo verification procedure with undamaged seals on FlS.