Siemens S7-300 - Checklist for General CP Functions; Communications Connection Checklist

STEP 7 special diagnostics
12.6 Checklist for "typical problems" in a system
Configuring and commissioning S7 CPs for Industrial Ethernet
214 Configuration Manual, 09/2013, C79000-G8976-C182-13
12.6.1
Checklist for general CP functions
Table 12- 3 Checklist for typical problems when operating a CP in a system
Problem
Possible cause
Identifying the cause and remedy
The Ethernet CP will not
change to the RUN mode.
Invalid configuration loaded on
the Ethernet CP.
Yellow STOP LED and red SF LED lit continuously.
Request for the diagnostics buffer in special
diagnostics.
Example of an entry:
CP STOP due to invalid CP parameter assignment
What to do:
Correct the configuration of the Ethernet CP.
Switch set to STOP on the
Ethernet CP
(only CPs with RUN/STOP
switch)
Request for the operating mode in special diagnostics.
Operating mode: STOP, cause: switch set to STOP
What to do:
Change the switch to RUN on the Ethernet CP
12.6.2
Communications connection checklist
Table 12- 4 Checklist for typical problems with ISO transport / ISOonTCP / UDP connections in a system
Problem
Possible cause
Identifying the cause and remedy
No data transfer on an ISO
transport connection /
ISOon
TCP connection or only
in one direction.
AGSEND and AGRECV are
not called in the user program.
or
Receive or
send buffer too small or
incorrect.
Check the user program.
Evaluate status bytes in AGSEND and AGRECV.
What to do:
If necessary, configure program blocks.
If necessary, correct ANY pointer.
The connection is not
established.
Evaluate status bytes of the program blocks or evaluate
diagnostics buffer.
What to do:
Change the address parameters (MAC/IP address,
TSAP).
Data transfer too slow Receiving device too slow
Evaluate diagnostic buffer.
Entry: "No receive resources on destination station XX".
What to do:
Delay the send trigger or check the destination station
and optimize reception.
The complete data field is not
sent on an ISO transport /
ISOonTCP/UDP connection.
LEN parameter for AGSEND is
set to the wrong value.
What to do:
Set the LEN parameter to the required size.
The complete data field is not
sent on an ISO transport /
ISOonTCP/UDP connection.
The buffer specified with the
ANY pointer is too small.
What to do:
Correct the LEN parameter and the ANY pointer.