Distributed over all the automation systems connected to the BCS, the BCS can:
● Have a brief peak load (max. 1 s) of up to 200 simultaneous step changes. In this case, a
maximum of 200 recipe phases that do not execute a step change can also be active. To
ensure that the BCS and AS continue to operate synchronized with each other following
such peak loads, you must ensure a recovery time of that least 60 s.
● Be run in continuous operation with not significantly more than 350 simultaneous, active
recipe phases. In this case, an average of 2 step changes may be active per second.
Result of the determination of memory requirements (data blocks) for AS-based mode
The following table shows the minimum memory requirements (data blocks) of the CPU for
AS-based mode.
Memory allocations Description Memory requirements in KB
Static part. Occupied by system. Communication (Event Send) 56
Function blocks 60
Function calls 41
Dynamic part. Occupied by settings in
the BATCH configuration dialog.
per unit 57
per recipe unit procedure (RUP) 128
Based on the recipe data from the section "Basics for calculating the performance of both
modes", the actual memory requirements can be calculated as shown below.
Note
For this performance determination, the units must be configured within one automation
system and the recipe unit procedures must all be active at the same time.
Sample calculation (AS-based mode only)
Memory allocations Description Memory requirements in KB
Static part. Occupied by system. Communication (Event Send) 56
Function blocks 60
Function calls 41
Dynamic part. Occupied by settings in
the BATCH configuration dialog.
10 units 570
10 simultaneously running recipe unit
procedures (RUP)
1280
Memory requirements Total in KB: 2007
Based on this calculation, it can be seen that the AS requires at least 2007 KB of memory for
the recipe logic. You set the memory required for the recipe logic as a percentage of the entire
work memory in the BATCH configuration dialog for the CPU.
To determine the amount of required memory for a CPU, you need to add the standard BATCH
blocks (SFC type, SFC, IEPH etc.) and the blocks for process control (drivers, actuators,
sensors etc.).
Product introduction and installation
3.6 Configuration limits
SIMATIC BATCH V8.2
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