Siemens SIMATIC S7-400H - Diagnostics of the CPU 41 X as DP Master; Diagnostics Using Leds; Meaning of the BUSF Leds of the CPU 41 X as DP Master

Installation of a CPU 41x-H
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Automation System S7-400H Fault-tolerant Systems
A5E00068197-07
• Reconfiguration of I/O modules, e.g. selection of other interrupt limits
• Reversal of modifications: added modules, DP slaves and PA slaves (field
devices) can be removed.
4.9.3 Diagnostics of the CPU 41x as DP Master
Diagnostics Using LEDs
Table 4-6 explains the meaning of the BUSF LED.
The BUSF LED assigned to the interface configured as the PROFIBUS DP
interface will always light up or flash.
Table 4-6 Meaning of the BUSF LEDs of the CPU 41x as DP master
BUSF
Meaning What to Do
Off Configuration correct
All the configured slaves are
addressable
–
Lights • Bus fault (hardware fault) • Check the bus cable for a short circuit or
interruption.
• DP interface fault
• Different transmission rates in
multi–DP master operation (only in
single mode)
• Evaluate the diagnosis. Reconfigure or correct
the configuration.
Flashes • Station failure
• At least one of the assigned slaves is
not addressable
• Check whether the bus cable is connected to
the CPU 41x or whether the bus is interrupted.
• Wait until the CPU 41x has powered up. If the
LED does not stop flashing, check the DP
slaves or evaluate the diagnosis of the DP
slaves.