Determination Of The Monitoring Times; Time Response During The Update; Determination With Step7 Or Formulas - Siemens SIMATIC S7-400H Manual

Time response during the update

The transfer time during updating depends on the number and overall length of the
modified data blocks; it does not depend on the modified volume of data within a
block. It is also dependent on the current process
state and on the communication load.
In a simplified view, the max. blocking time to be configured for priority
classes > 15 can be seen as a function of the volume of data in the main memory.
The volume of code in the main memory is irrelevant.
6.3.2

Determination of the Monitoring Times

Determination with STEP7 or formulas

The monitoring times listed below are automatically calculation by STEP 7 in
version 5.2 or later for each new configuration. You can also calculate them using
the formulas and procedures described below. They are equivalent to the formulas
used in STEP7.
• Maximum scan-cycle time extension
• Maximum communication delay
• Maximum retention time for priority classes
• minimum I/O retention time
You can also automatically calculate the monitoring times in HW Config in the
dialog Properties CPU –> Trigger H Parameters.
Automation System S7-400H Fault-tolerant Systems
A5E00068197-07
Linking and Synchronizing
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