Siemens Simatic S7 Series

Special memory (SM) and system symbol names
D.10 SMW22-SMW26: Scan times
S7-200 SMART
System Manual, 09/2015, A5E03822230-AC
673
D.10
SMW22-SMW26: Scan times
SMW22, SMW24, and SMW26 contain information on the scan time. You can read the last
scan time, minimum scan time, and maximum scan time (millisecond values).
Table D- 7 SMW22-SMW26 PLC scan times
S7-200 SMART
symbol name
SM address
Description
Last_Scan
SMW22
Scan time of the last scan.
Minimum_Scan SMW24 Minimum scan time recorded since entering the RUN mode or since resetting these
values from the PLC Information dialog.
Maximum_Scan SMW26 Maximum scan time recorded since entering the RUN mode or since resetting
these values from the PLC Information dialog.
D.11
SMB28-SMB29: Signal board ID and errors
SMB28-SMB29 byte addresses store the signal board type and error status.
See also
SMW100-SMW110 System alarm codes (Page 684)