Siemens CP 1243-8 IRC, Руководство по эксплуатации

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Configuration and operation
4.7 Configuration in STEP 7 Basic
CP 1243-8 IRC
Operating Instructions, 06/2015, C79000-G8976-C385-01
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● Cycle pause time
This is the waiting time between two scan cycles. It is used to reserve adequate time for
other processes that access the CPU via the backplane bus of the station.
Duration of the CPU scan cycle
Since no fixed time can be configured for the cycle and since the individual phases cannot
be assigned a fixed number of objects, the duration of the scan cycle is variable and can
change dynamically.
4.7.14 "Trigger“ tab
Trigger
Data points are configured as a static value or as an event using the "Type of transmission"
parameter:
Saving the value of a data point configured as an event
Saving the value of a data point configured as an event in the send buffer (message
memory) can be triggered by various trigger types:
● Threshold value trigger
The value of the data point is saved 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 76).
● Time trigger
The value of the data point is saved at configurable intervals or at a specific time of day.
● Event trigger (Trigger tag)
The value of the data point is saved when a configurable trigger signal is fired. For the
trigger signal, the edge change (0 → 1) of a trigger tag is evaluated that is set by the user
program. When necessary, a separate trigger tag can be configured for each data point.
Resetting the trigger tag in the bit memory area / DB:
If the memory area of a trigger tag is in the bit memory or in a data block, the value “1” of
the trigger tag is reset to zero when the data point value is transferred.
Transferring the value of a data point configured as an event
You specify whether the value of a data point is transferred to the communications partner
immediately after the trigger fires or after a delay in the "Transmission mode" parameter.