The CPU Performs a Consistency Check of the Configuration Changes

First, the CPU determines the number of DP and PA master systems at which you

want to add/remove slaves/modules or modify assignments in the existing process

image partition. If the CPU finds a maximum of four affected master systems it

continues the check. If more than four are found, the CPU will reject the modified

configuration.

In the next test the CPU calculates the CiR synchronization time as follows:

•

If you only want to change the parameters of existing modules, then the

following applies regardless of the type of CPU:

CiR synchronization time for the CPU = 100 ms

In all other cases the following applies:

The CiR synchronization time of the CPU is proportional to the cumulative CiR

synchronization times of all relevant master systems.

Relevant master systems the systems at which you add/remove slaves or

modules or modify the process image partition assignment.

•

CiR synchronization time of a relevant master system = basic master system

load + the total I/O volume of the master system in bytes * time per byte. The

total I/O volume of the master system in bytes is composed of the sum of

physically existing I/O bytes and the I/O bytes of the CiR elements at this

master system. The system load for the each CPU type used to calculate the

required load for the master system and the time per byte can be found in the

technical data for your CPU.

Note

•

In this case the calculation of the CiR synchronization time is based on a

worst-case scenario. This means that during a CiR operation the actually

incurred CiR synchronization time is always lower or equal.

•

The CiR synchronization time for a master system is shown in HW Config in

the properties window for the associated CiR object.