Siemens Sinumerik 840DiE sl - Testing the PLC Program

01/2007
6.7 Testing the PLC program
6-156
© Siemens AG 2007 All Rights Reserved
SINUMERIK 840Di sl Manual (HBIsl) – 01/2007 Edition
6.7 Testing the PLC program
6.7.1 Start–up behavior
Start–up of a SIMATIC–CPU module can be set for the following start–up modes:
– Restart
– Cold restart (warm restart)
– Cold restart
With a SINUMERIK 840Di sl, the start–up type of the PLC is permanently set
to
RESTART
. It cannot be changed.
With COLD RESTART block ”OB100” is executed first. Then cyclic operation
starts with call–up of block ”OB1”.
The following data are kept in the case of COLD RESTART:
– All data blocks and their contents
– Retentive timers, counters and flags
The ranges of the timers, counters and flags that are to be retentive must be set
using the dialog box Properties, tab Retention of the PLC–CPU module.
Notice
The retention of the data areas can only be achieved with the backup supply
(backup battery) active. If the battery backup is empty, the PLC will not restart.
The following operations are performed during a restart:
– UStack, BStack and non–retentive flags, timers and counters will be
deleted
– The process output image (POI) will be deleted
– Process and diagnostics alarms will be canceled
– The system status list will be updated
– Parameterization objects of modules (from SD100 onwards) will be
evaluated or defaults parameters will be output to all modules in single–
processor mode
– OB100 (cold restart) is executed
– The process input image (PII) is read in
– The command output disable (COD) is canceled
Start–up mode:
RESTART
Retentive ranges
6 PLC Commissionin
g