4. Configuration
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ATTENTION:
The SNTP service depends on the user application only for its configuration. This service will run
even when the CPU is in STOP or BREAKPOINT mode, since there is an application in the CPU
with the SNTP client enabled and properly configured.
CAUTION: It is vital the configuration of at least one SNTP server if IRIG-B synchronism
method isn’t used. It is recommended to set two SNTP servers (primary and secondary). The
SNTP synchronism is necessary to generate events with coherent time stamp between CPUs A
and B and with world time. Another purpose is to avoid discontinuity during a switchover in
applications that reference date and time, considering that there is no synchronism of date and
time between the CPUs through redundancy synchronism channels.
Daylight Saving Time (DST)
The DST configuration must be done indirectly through the SetTimeZone function, which changes
the time zone applied to the RTC. In the beginning of the DST, this function is used to increase the
time zone in one hour. At the end of the DST, it is used to decrease it in one hour.
For further information, see RTC Clock – Function Blocks and Functions for RTC Reading and
Writing.
Internal Points
A communication point is stored on the RTU memory in two different variables. One of them
represents the point value (type BOOL, BYTE, WORD, etc…), while the other represents its quality
(type QUALITY). Internal Points are those which value and quality are calculated internally on the
user application, i.e., does not comes from an external source like happens for points associated to
some IED (Master/Client communication drivers) or to some I/O module.
The objective of this Internal Points configuration tab is to create a relationship between the variable
which represents the value of a given point and the variable which represents its quality. It should be
used to link the value and quality variables created internally on the RTU program (like the variables
created on a GVL), which later will be typically mapped to a Server communication driver for
communication with control centers.
ATTENTION:
If a value variable do not own a related quality variable, it will report, by default, a constant good
quality (no significant indication) when the variable get reported to a client or control center.
Then, the objective of this tab is not to create or to declare internal points. For this, it is just needed to
declare the value and/or quality variables on a GVL and map it to a communication driver.
The configuration of the internal points (Figure 4-3), follows the parameters described in Table 4-6.
The user can set up to 5120 inputs in the Internal Points table.
Figure 4-3. Internal Points Settings
