Siemens SIMATIC HMI OP3, Equipment Manual

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4-2
Operator Panel OP3
Edition 11/99
The change from screen level to message level, or back again, is either
manual or automatic.
You press the appropriate key and change the operating level
•
from message level to screen level by pressing the ENTER key,
•
from screen level to message level by pressing the ESCAPE key.
You cannot branch backward from the message level by pressing
ESCAPE
.
The key is merely designed to terminate the display of a system message at
this level. Figure 4-1 shows how you switch from one operating level to the
other.
Message level
Screen level
⇓
⇑
ESC
System message
ENTER
Figure 4-1 Changing between Message Level and Screen Level
The OP3 returns immediately to the temporary message level when a
message arrives. If the message is acknowledged by pressing
ENTER or if it
departs, the very same screen from which the OP3 branched to the message
level is displayed again. If several messages arrive simultaneously, all
messages are acknowledged by pressing
ENTER .
All inputs not confirmed by pressing ENTER before the OP3 branched to
message level are canceled.
If several messages are queuing, you can view several messages in
succession by scrolling with the
UP and DOWN keys. Only UP , DOWN and
ENTER are allowed at the temporary message level.
If you jump from one screen to another, the OP3 can retain a total of twenty
jumps. You return by pressing
ESCAPE
.
If the nesting level of twenty screens is exceeded, the OP3 jumps –
subsequent to a temporary message display – to the twentieth screen, not to
last screen that was called.
Changing
operating levels
Manual change
Automatic change
Operation in the
temporary
message level
Nesting level
Using the OP3 with Its Standard Functions