Siemens Simatic S7-1500 Function Manual page 63

Cycle and response times of the S7-1500R/H redundant system
5.3 Influences on the cycle time of the S7-1500R/H redundant system
Differences between the synchronization times
The available bandwidth has a significant impact on the synchronization time.
With the R-CPUs both the synchronization of data and the synchronization of communication
tasks operate over the PROFINET ring. 25% of the bandwidth is reserved for the
synchronization.
With the H-CPU, synchronization works independently of the PROFINET ring over fiber optic
cables. The full bandwidth on the PROFINET cable is available for PROFINET IO
communication.
The table below provides an overview of performance features of R-CPUs and H-CPU.
Table 5- 1 Performance features of S7-1500R and S7-1500H
Performance
•
•
•
Hardware
•
•
•
•
Technical specifications
More information about the technical specifications is available in the manuals of the specific
CPUs.
62
S7-1500R
CPU 1513R-1 PN
Data transfer rate of 100 Mbps (for synchronization
and communication)
Data work memory: max.
1.5 MB
Code work memory:
max. 300 KB
The CPUs are identical in design with the respective
S7-1500 standard versions.
The synchronization of the CPUs takes place over the
PROFINET ring.
The H-Sync-Forwarding function is recommended for
all devices in the PROFINET ring.
Part of the bandwidth on the PROFINET cable is
used to synchronize the CPUs. Less bandwidth is
therefore available for PROFINET IO communication.
CPU 1515R-2 PN
Data work memory:
•
max. 3 MB
Code work memory:
•
max. 500 KB
S7-1500H
CPU 1517H-3 PN
Significantly greater performance than
•
S7-1500R due to
– Separate redundancy connections
over fiber-optic cables
– Greater computing power
Transmission rate of 1 Gbps (for the
•
synchronization)
Data work memory: max. 8 MB
•
Code work memory: max. 2 MB
•
The CPUs each have two optical inter-
•
faces.
The synchronization of the CPUs
•
operates independently of the
PROFINET ring over fiber-optic ca-
bles.
The full bandwidth on the PROFINET
•
cable is available for PROFINET IO
communication.
Cycle and response times
Function Manual, 10/2018, A5E03461504-AD