Landis+Gyr ZFQ202, User Manual

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Gyr H 71 0200 0215 f en - ZMQ202 / ZFQ202 - User Manual
24/88 Description of Unit
2.6.2 Adjsuting the Calendar Clock via Communication
The calendar clock can be adjusted by the central station, which sends the
time information to the meter via the selected communication interface.
The time information received from the central station is compared with
the local time of the meter. The reaction of the meter to the time
information depends on the deviation.
The time can be adjusted as often as required but only once per capture
period.
Note
Time adjustment twice within capture period
If the time is adjusted a second time within the same capture period, the
capture period is reset no matter how small the deviation.
This is to prevent multiple adjustment with a small time shift resulting in a
large time shift that, if made in one single approach, would have reset the
capture period.
2.6.3 Handling the Deviations
Depending on the time deviation of the internal clock from the external
master clock, the adjustment has different effects on the calendar clock.
The following cases are possible:
• the time deviation is between 0 second and 2 to 9 seconds (depending
on parameter setting)
• the time deviation is longer than 2 to 9 seconds (depending on
parameter setting)
- time setting
- capture period reset
- synchronisation
- time shift
0 s 2 ... 9 s Deviation
The effects of the adjustment are the same, no matter whether it was
triggered by a pulse or via communication.
If the difference between the internal clock and the master clock is
between 0 seconds and a maximum of 9 seconds, the time is advanced or
set back by the corresponding period of time. Advancing or setting back
the clock is only allowed once per capture period. The capture period is
shortened or elongated by the length of the time shift.
If the difference between the internal clock and the master clock is longer
than 2 to 9 seconds, the time will be reset to either the start time or the
end time of the capture period. The affected capture period is declared as
invalid.
Between 0 seconds
and 2 to 9 seconds
Longer than 2 to 9
seconds