Table 5-1 Leds On The Cpus - Siemens SIMATIC S7-400H System Manual

LED displays
The following shows you an overview of the LEDs on the individual CPUs.
Sections Monitoring functions of the CPU (Page 44) and Status and error displays (Page 46)
describe the states and errors/faults indicated by these LEDs.
Table 5-1
LED
INTF
EXTF
FRCE
RUN
STOP
BUS1F
BUS2F
MSTR
REDF
RACK0
RACK1
IFM1F
IFM2F
Mode selector switch
You can use the mode selector switch to set the current mode of the CPU. The mode selector
switch is a rocker switch with three positions.
Section Mode selector switch (Page 49) describes the functions of the mode selector switch.
Memory card slot
You can insert a memory card into this slot.
There are two types of memory card:
● RAM cards
● Flash cards
S7-400H
System Manual, 09/2007, A5E00267695-03
LEDs on the CPUs
Color
Red
Red
Yellow
Green
Yellow
Red
Red
Yellow
Red
Yellow
Yellow
Red
Red
You can expand the CPU loading memory with the RAM card.
A FLASH card can be used for fail-safe backup of the user program and data without a
backup battery. You can program the flash card either on the programming device or in
the CPU. The flash card also expands the load memory of the CPU.
For detailed information on memory cards, refer to section Structure and Functions of the
Memory Cards (Page 54).
5.1 Control and display elements of the CPUs
Meaning
Internal error
External error
Active force request
RUN mode
STOP mode
Bus fault on MPI/PROFIBUS DP interface 1
Bus fault on PROFIBUS DP interface 2
CPU controls the process
Redundancy loss/fault
CPU in rack 0
CPU in rack 1
Error in synchronization module 1
Error in synchronization module 2
Installation of a CPU 41x–H
41