Siemens SIMATIC NET TeleControl S7-1200 CP 1243-1 Operating Instructions Manual page 77

When data points are configured as an event via the "Type of transmission" parameter,
the following event classes are available:
– Every value triggered
– Current value triggered
Trigger
Trigger types
Various trigger types are available for event-driven transfer:
● Threshold value trigger
The value of the data point is transferred when this reaches a certain threshold. The
threshold is calculated as the difference compared with the last stored value, refer to the
section Threshold value trigger (Page 79).
● Time trigger
The value of the data point is transferred at configurable intervals or at a specific time of
day.
● Event trigger
The value of the data point is transferred when a configurable trigger signal is fired. As
the trigger signal, the edge change (0 → 1) of a trigger bit is evaluated that is set by the
user program. When necessary, a separate trigger bit can be configured for each data
point.
Resetting the trigger tag in the bit memory area / DB:
If the memory area of the trigger tag is in the bit memory or in a data block, the trigger tag
is reset to zero when the data point value is transferred.
Transmission time of the frame (Transmission mode)
Whether the value of a data point is transferred to the communications partner immediately
after the trigger fires or after a delay depends on the setting of the parameter "Transmission
mode" in the "Trigger" tab of the data point:
● Spontaneous
The value is transferred immediately.
● Conditional spontaneous
The value is transferred only when one of the two following conditions is fulfilled:
– The telecontrol server queries the station.
– The value of another event with the transmission mode "Unsolicited" is transferred.
CP 1243-1
Operating Instructions, 12/2016, C79000-G8976-C365-02
Each value change is entered in the send buffer in chronological order.
Only the last current value is entered in the send buffer. It overwrites the value stored
there previously.
Configuration
4.9 Data points
77