Technical Data - Siemens S7-1200 Manual

6 LCCF_EnetScanner block
6.1.2

Technical data

For better planning of the automation program the user must be aware, that the
operation of the LCCF_EnetScanner block has impacts on both memory loading
and cycle time of the remaining automation program.
As all the protocol handling is done as part of the user program, the cycle time will
be extended by the time the selected CPU model requires to execute the protocol
stack. As one could imagine the more adapters are configured the more time is
necessary to compute the communications. Another performance influencing factor
is the RPI. The shorter the RPI is, the more often communication to the adapters
need to be done.
Figure 6-1: PLC load depending on RPI and number of adapters
7
5
3
1
500
The above diagram doesn't show real loadings nor do the value are based on
NOTE
real measurements for a specific CPU.
The diagram only illustrates the loading dependencies.
As shown in the above diagram, lower RPI cause more updates per time unit. This
in turn causes a higher load o the PLC. The number of configured adapters also
has an influence on the PLC load in the way, that the higher the number is, the
higher the load will be (proportional).
EtherNet/IP Scanner
Entry-ID: 109782314, V1.1.0,
50
100
200
04/2021
10
20
25
100
90
80
70
60
50
40
30
20
10
0
5
41