Siemens S7-200 System Manual page 118

Operating Your Text Display (TD) Device
5.5 Viewing the Screens and the Alarms
Bits Associated Enable Condition
with Alarms and for the Bit
Screens
ALARM Alarm
ACKNOW- acknowledgement
LEDGE is available only if
the wizard
configuration has
the option enabled
for this alarm:
Alarm should
require operator
acknowledgement
118
Results shown on the TD Display
The user acknowledges an alarm message by
scrolling to the message and pressing the
ENTER key. The TD device will then set the
acknowledge notification bit in the CPU and the
alarm message will stop flashing (blinking).
If there are no editable variables in the message
the TD device will also clear the alarm enable bit
for this message.
If there are editable variables in the message, the
user must either edit the variables (change them
and press ENTER) or accept the current values
(press ENTER). When the last variable in the
message is edited or accepted, the TD device will
write the variable to the CPU and clear the alarm
enable bit.
If the user does not complete editing the
variables in the message, the TD device will
begin to flash (blink) the message to notify the
user that an action is still pending.
Clear Condition for the Bit
The TD device will set the
alarm acknowledge bit. The
user program logic must
clear the alarm
acknowledgement bit.
Text Display (TD) User Manual
System Manual, 08/2008, A5E00765548-03