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Standard Mode
Section 4-9
4.9.2 External Messages
External messages are generated by the connected controller and forwarded to the
operating terminal as information on the monitored process. The user can choose
two separate message systems. Depending on the requirements, message trans-
fers to the operating terminal can be either serial or parallel, regardless of whether
the messages are process or fault messages.
Messages can consist of the message text and a scaled and formatted variable.
Every variable type available in the system is valid.
The information in the message memory can be used for statistical evaluations.
The message is assigned between the terminal and the controller by means of a
message number. The associated texts and variable specifications are stored in
the terminal together with the user description. The function of a message and its
contents are determined by the user when the user description is created in the
programming system.
All of the external messages are stored in the message memory in chronological
order or in order of priority. In addition parallel messages can optionally be stored in
the serial message memory and as a result also evaluated statistically. If the mess-
age contains a variable, its value will be frozen in the message memory.
4.9.2.1 Structure of an External Message
An external message is made up of:
-
a message number between 1 and 9999
- a message text with up to 255 characters
- one variable at maximum.
When creating a new application, existing messages (one or all) are reusable.
4.9.2.1.1 Assigning Message Numbers
With external messages, message numbers also determine the priority of a mes-
sage, with message no. 1 being the highest and message no. 9999 being the low-
est priority. It is not necessary that message numbers are assigned contiguously;
this allows messages with related contents to be grouped.
The assignment of message numbers for status messages always starts with ‘1’.
Make sure that the serial and parallel message system do not overlap. If the two
message systems are to be independent from one another, ensure that the mes-
sage numbers for the serial system start above those for the status messages. In
addition, message numbers and mask numbers must be coordinated accordingly
when the programming is carried out (see chapter 4.9.2.3.1
Full-Page Message
Output).
The system allows status message texts to be used in the serial message system.