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5.1.2.7 Clock calendar configuration (for X3M-D only)
The X3M-D is equipped with a clock/calendar with internal battery having a 15 years life time.
The clock/calendar supports the time zone handling functions and the automatic change from Standard Time
to Daylight Saving Time and vice versa.
The instrument is set by default to the Europe/Rome time and time zone.
The clock/calendar setting is covered by the last two SETUP pages.
Clock format
The following Time formats are foreseen:
Coordinated Universal Time (UTC):
commonly known as GMT (Greenwich Mean Time): it is the
universal time, applicable to any place on earth.
Standard Time:
it is the local time of a specific time zone, based on the sun cycles (known as Solar
Time
Daylight Saving Time
it is the local time of a specific time zone
when an offset on standard time is
applied (DST offset). The introduction of this offset allows to increase the availability of hours with
natural light in the summer evenings.
Wall time:
it is how we refer to the clock time in each time zone. The Wall time actually coincides with
the Daylight Saving Time or the Standard Time depending whether an offset Solar time is
occurring or not.
The difference between Standard Time and UTC time is called GMT offset.
Summarizing:
GMT offset = UTC – Standard Time
Wall Time = Standard Time + DST offset = UTC + GMT DST offset
The instrument RTC supports the following time information:
•
UTC
Date/time
•
Time zone identification
Starting from the UTC time, the instrument automatically calculates the local time (Wall Time) of any place
on earth
The pertinent time zone is entered to the instrument by a numeric index (time zone index) either on the set
up procedure or on a MODBUS register.
NOTE:
The instrument clock operates in UTC, therefore a correct time zone attribution is essential. Check
whether the time zone entry is correct before modifying the clock. Otherwise a wrong time setting
could be involuntarily programmed
The clock is updated by using the local time or “wall time” that the instrument converts in UTC, consequently,
if the time zone is wrong, the clock will be wrong too.
(1) It identifies the time programming page N° 1.
(2) Time zone 334 = Europe/Rome is valid all over central Europe. See the enclosed layout to identify
the right time zone
