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
Behavior following specific events in redundancy mode
Event
Reaction
Master to standby switchover
with modified configuration
The bus link is switched bumplessly from the active Compact FF Link
to the previously passive Compact FF Link.
Failure of a CPU
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.
Failure of a Compact FF Link
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.
Failure of the active 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.
Failure of the passive channel. No effect on the bus link. A diagnostic message is generated in the
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.
Operation of the bus link
8.3 Behavior after certain events in the redundancy mode
Compact FF Link
44
Operating Instructions, 03/2015, A5E35651552-AA