Siemens SENTRON PAC4200, Руководство пользователя, Страница: 40 / 252

Description
3.7 Date and time
SENTRON PAC4200
40
Manual, 09/2008, A5E02316180B-01
3.7 Date and time
UTC time and local time
The internal clock of SENTRON PAC4200 measures UTC time. All information about the
date and time (time stamp) that can be called at the communication interfaces must be
interpreted as UTC time.
The SENTRON PAC4200 display indicates the configured local time corresponding to the
time difference due to time zones and daylight saving time.
UTC time: Universal Time Coordinated (UTC) is the international reference time.
Time zone: Geographical areas with the same positive or negative deviation from UTC time
are grouped together in time zones.
Local time: Local time is UTC time plus or minus the time difference due to the time zone
plus or minus the time difference due to the locally applicable daylight saving time.
Example: 3.36 p.m. CEST (local time in Germany) on September 10, 2008 corresponds to
1.36 p.m. (UTC time) on September 10, 2008. Germany is located in the UTC+1 time zone.
Daylight saving time applies on the above-mentioned date, so that the local time difference is
increased by one hour ("+1").
Synchronization of the internal clock
The internal clock of SENTRON PAC4200 can be synchronized with an external time, e.g.
with the "Top of minute" pulse or with a synchronization command via the available
communication interfaces.
Synchronization is relevant for all measured variables where the time of occurrence is also
captured, e.g. for recording the load profile.
3.8 Limit values
SENTRON PAC4200 monitors up to 12 limit values as well as one limit that can be formed
by logically combining the other 12 limits.
Defining the limit values
The number of limit values to be monitored is selectable. The following must be specified for
each of the maximum of 12 limit values:
●
Limit value monitoring ON/OFF
● Monitored measured variable
● Threshold
● Upper or lower limit violated
● Time delay
● Hysteresis