Flowmeter SVTU-11B, Руководство по эксплуатации

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12 Servicing
12.1 The Instruction to the representative of inspecting service
12.1.1 The SVTU-11B water meter is protected from consumer intervention as well as
intervention of heat supply organization. Any changes of a water meter parameters can be
carried out only in
‘Setup’ and ‘Verification’ service modes. To except a non-authorized
access into device functioning process and prevent possible attempts to change any device
constants (calibration factors of thermoresistor Kdl and Krc, flow rate conversion ratio,
geometrical parameters of a flow meter), the fact of login or running through these modes is
fixed in the
‘Check’ mode. The opportunity to check inputs in the specified modes is
equivalent to a mechanical sealing (i.e. it substitutes mastic seals, branded labels, etc.), so it
is
electronic way of sealing of the calculator . Therefore the basic attention should be paid
to the number of entries into service modes. Difference of this number from the recorded
one at the moment of device commissioning (release date according to the certificate) should
be considered as damaging of the seal installed by inspecting organization. The possibility of
mechanical sealing of the calculating unit with the use of sealing cups with holes on device
case is stipulated. So, the fact of intervention in device functioning should be registered by
analysis of event journal. All user’s actions, which lead to change in device readings are
dated in the event journal. If the event journal has a record about entering into service mode,
but no records about meter parameters changing, it means that the user logged in and imme-
diately logged out without changing meter parameters and performance.
12.1.2 In doubts of correct installation or proper operation of the water meter it is ne-
cessary to run ‘Check’ mode and to compare correctness of the entered values for RTD tem-
perature coefficients, FS exact diameters, distances between flow sensor transmitters and FS
conversion ratios to data resulted in Chapter 17 ‘Parameters and characteristics of meter
components’. Thus compared values can differ in limits, which are not exceeding units men-
tioned in Chapter 17 of this OM.
12.1.3 It is necessary to consider, that water meter commissioning begins with reset
(zeroing) of its integrated indications (accumulated measuring data) on setting account mode
to “In account”. Reset of indications also should be carried out after meter repair or verifica-
tion.
12.1.4 Difference between power on time and time of correct work means that a water
meter operated incorrectly (switching-off, breakage or short circuit of sensor cables, absence
of the water, etc., see item 10.8). Therefore sealing of flow sensors or their connectors is not
obligatory. However, the possibility of mechanical sealing for flow sensors and their connec-
tors with a use of proper holes in clamping nuts of FlS and connector housings is stipulated.
12.1.5 To except a non-authorized influence on RTD parameters and so on temperature
measurement accuracy it is necessary to mechanically seal up the temperature sensor using a
hole in RTD housing.
12.2 Maintenance service is carried out by the representative of service organization.
During servicing it is necessary to carry out the security measures interpreted in Chapter 8.