Startup With Cpu; Behavior After Certain Events In The Redundancy Mode - Siemens SIMATIC Compact FF Link Operating Instructions Manual

Operation of the bus link

8.3 Behavior after certain events in the redundancy mode

8.2

Startup with CPU

Startup characteristics
The following cases are distinguished:
● Once it is detected that all FF devices are available in accordance with the configuration,
all output data is transferred and all input data is reported to the CPU.
● If at least one FF device does not correspond to the configuration (not available, or incorrect
name), the startup delay is maintained. The I/O data is then enabled for all FF devices with
error-free configuration (previously "0") and relevant interrupts (removal or diagnostic
interrupt) are reported for incorrectly configured FF devices.
You must set the startup delay according to the size of your system configuration in the
properties dialog of Compact FF Link.
8.3 Behavior after certain events in the redundancy mode
Behavior of the Compact FF Link
The following table shows the response of Compact FF Link to specific events when operating
in redundancy mode.
Table 8-1
Event
Master to standby switchover
with modified configuration
Failure of a CPU
Failure of a Compact FF Link
Failure of the active channel.
Failure of the passive channel. No effect on the bus link. A diagnostic message is generated in the
44
Behavior following specific events in redundancy mode
Reaction
The bus link is switched bumplessly from the active Compact FF Link
to the previously passive Compact FF Link.
If this also leads to a failure of the active channel of the redundant DP
master system: see failure of the active channel.
Otherwise: see failure of the passive channel.
A diagnostic message is generated in the system.
If the active Compact FF Link fails, there is a bumpless switchover to
the previously passive channel.
The bus link is switched bumplessly from the active Compact FF Link
to the previously passive Compact FF Link.
The failed channel is displayed on the associated Compact FF Link:
● "BF DP" LED: Failure of the PROFIBUS channel.
● "BF FF" LED: Failure of the FF channel.
system.
The failed channel is displayed on the associated Compact FF Link:
● "BF DP" LED: Failure of the PROFIBUS channel.
● "BF FF" LED: Failure of the FF channel.
Operating Instructions, 03/2015, A5E35651552-AA
Compact FF Link