Siemens SINUMERIK 840Di Function Manual page 934

Detailed description
2.4 Starting up the PLC program
NC variables
The latest NC VAR selector can be used for each NC software version (even earlier
versions). The variables can also be selected from the latest list for earlier NC software
versions. The data content in DB 120 (default DB for variables) does not depend on the
software version, i.e., selected variables in an older software version must not be reselected
when the software is upgraded.
2.4.8 I/O modules (FM, CP modules)
Special packages for STEP7 are generally required for more complex I/O modules. Some of
these special packages include support blocks (FC, FB) stored in a STEP7 library. The
blocks contain functions for operating the relevant module which are parameterized and
called by the user program. In many cases, the FC numbers of the CP and FM module
handling blocks are also included in the number range of the basic program for the 810D and
840D systems.
What action can be taken if such a conflict occurs?
The block numbers of the basic program must remain unchanged. The block numbers of
handling blocks can be assigned new, free numbers using STEP7. These new blocks (with
new FC numbers) are then called in the user program with the parameter assignments
required by the function.
2.4.9 Troubleshooting
This section describes problems which may occur, their causes and remedies and should be
read carefully before hardware is replaced.
Errors, cause/description and remedy
Serial
no.
error
inform
ation
1
2-22
Error Cause/description
No The MPI cable is not connected
connecti or is defective.
on via
MPI to
PLC.
The STEP 7 software for the
MPI card may not be configured
correctly.
Remedy
Test: Create a link with the programmer in the
STEP 7 editor by means of connection
"Direct_PLC". A number of node addresses
must be displayed here. If they are missing,
the MPI cable is defective or not connected.
In Windows 95 versions of STEP 7, the
hardware must be checked in the Control
Panel; the PC/PG interface configuration
should also be checked as well.
Power Line Basic PLC Program (P3)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0