Failure Of One Redundancy Connection And The Primary Cpu In S7-1500H - Siemens SIMATIC S7-1500 System Manual

6.5.4.2

Failure of one redundancy connection and the primary CPU in S7-1500H

Introduction
The following failure scenario describes the effects of a defect in a redundancy connection
and the primary CPU in S7-1500H using a PROFINET ring as example. In this failure scenario,
the time between the failure of the redundancy connection failure and of the primary CPU is
> 55 ms.
Failure scenario
①
②
③
④
⑤
⑥
Figure 6-54
Sequence of events
1. One of the two redundancy connections is interrupted.
2. Availability is restricted. The redundant system will remain in the RUN-Redundant system
state.
3. The primary CPU also fails. Due to the failure, the primary CPU is no longer visible for the
backup CPU.
S7-1500R/H redundant system
System Manual, 01/2024, A5E41814787-AF
Primary CPU → failed (2nd failure in sequence of events)
Backup CPU
One fiber-optic cable (redundancy connection) → interrupted (1st failure in sequence of
events)
IO device ET 200SP
IO device ET 200MP
PROFINET cable (PROFINET ring)
Failure of one redundancy connection and the primary CPU
Application planning
6.5 Failure scenarios
213