Figure 4-5 startup – Siemens S5-135U/155U User Manual

Page 77

4-11

System Manual
C79000-G8576-C199-06

The following flowchart provides an overview of the sequence for startup
and validity check of a CC with CPU inserted and with no user program. For
the CPU 948, all steps relating to the memory submodule are skipped.

Connect power supply unit

Switch on supply voltage

CPU:

LED “BASP” on

LED “STOP” flashing fast

all others off

PS:

Correctly wired?

Voltage Present?

LED “Fan

Fault” on

LED

“Voltage
Low” on

Check load

voltage

connection

Check

Fan

CPU:

LED “STOP” on

LED “BASP” on

CPU:

LED ”BASP” on

LED “STOP” flashing fast

all others

off

Replace PS

Unit O.K.

Replace memory submodule

Reset CPU: Set to “Reset,”
switch from “STOP” to “RUN”

CPU:

LED “RUN” on,

LED “BASP” off

Memory

submodule:

correctly inserted?

Insert memory
submodule correctly

CPU general reset

PS:

LED “DC5V”

and “DC 24V” on, all

others off

Insert memory submodule in
CPU (not with the CPU 948)

CPU at “STOP”

Replace CPU

repeat startup

LED “MB

Low” on

LED “RB

Low” on

Check backup bty

and replace

if necessary

Replace

rechargeable

battery

Replace bty

compartment

Fault

corrected

Yes

Press

RESET
LED off

all others off

Press

RESET
LED off

Fault

corrected

Figure 4-5

Startup

Startup and
Validity Check

Central Controllers and Expansion Units Power Supply Units