LEDs INTF, EXTF and FRCE
The three LEDs, INTF, EXTF and FRCE, provide information about the errors and
special events during running of the user program.
LED
INTF
EXTF
H
x
x
H = LED lights up; x = LED status is irrelevant
LEDs BUSF1 and BUSF2
The LEDs BUSF1 and BUSF2 indicate errors in connection with the MPI/DP
interface and the PROFIBUS DP interface.
LED
BUS1F
H
x
B
x
H = LED lights up; B = LED flashes; x = LED status is irrelevant
Automation System S7-400H Fault-tolerant Systems
A5E00068197-07
FRCE
x
x
An internal error has been detected (programming or parameter
assignment error).
H
x
An external error has been detected (in other words, the cause of
the error cannot be traced back to the CPU module).
x
H
A force request is active.
BUS2F
x
An error has been detected at the MPI/DP interface.
H
An error has been detected at the PROFIBUS DP interface.
x
DP master:
One or more slaves at PROFIBUS DP interface 1
are not replying.
DP slave:
not addressed by the DP master
B
DP master:
One or more slaves at PROFIBUS DP interface 2
are not replying.
DP slave:
not addressed by the DP master
Installation of a CPU 41x-H
Meaning
Meaning
4-9