Step 8; Notes Relating To Multiprocessor Start - Siemens S5-155U System Manual

Starting the Multiprocessor Operation

Step 8

Possible faults
Notes relating to
multiprocessor start
6 - 14
Setting the coordinator mode switch to RUN or TEST:
IF...
You do not wish to set the coordinator
work in the mode switch from
1)
test mode STOP to RUN.
you wish to work in set the coordinator
the test mode (it must mode switch from
be enabled on the STOP to TEST.
1)
coordinator)
1)
Test mode and setting: see Section 6.3
Symptom:
All CPUs remain in the Stop state.
Remedy:
Check whether the mode switches of all CPUs are set to RUN.
A subsequent start of individual CPUs is not possible. Switch the
coordinator back to STOP. Execute a RESET at all CPUs and then
switch the coordinator to RUN again.
Note
During the starting phase (processing of the start OBs) the STOP
and RUN LEDs remain off at all CPUs. The RUN LED only
lights up continuously when the CPUs go over to cyclic program
processing.
• • When the coordinator is switched from STOP to TEST, only the
CPUs whose switches are at the RUN setting will operate in the
test mode.
• • If the 923C coordinator is used and the PG interface on the front
plate is not connected to the PG and switched online, the IF
FAULT LED lights up on the 923C coordinator. The indicator can
be ignored in this case.
THEN... Reaction
The green RUN
LEDs of all CPUs are
continuously lit. All
CPUs simultaneously
go into the cycle. The
output inhibit signal
is not emitted (BASP
LED = off).
set the coordinator
mode switch from
STOP to TEST.
System Manual
C79000-B8576-C199-03