If you interconnect several star structures, you obtain a tree network topology.
9.3 PROFINET system limits
Based on the devices, which have to communicate with the IO controller per ms, you can
determine the maximum number of devices. This also results in the maximum number of
configurable connections. The
Devices per ms
can be determined by the sum formula of
the individual refresh times (A).
D Devices per ms
n
Number of devices
A Refresh time device
The PROFINET IO controller has the following system limits
Devices per ms (D)
Max. number of devices
Max. number of configu-
rable connections
8
32
0
7
32
2
6
64
4
5
96
6
4
128
8
3
128
12
2
128
16
1
128
20
0
0
24
O Output bytes per ms
n
Number of devices
B Number output bytes per device
A Refresh time per device
Tree
Example network
Maximum number devices
and configurable connec-
tions
Output bytes per ms
System 300S
+
Deployment Ethernet communication - PROFINET
PROFINET system limits
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