Siemens Simatic S7-300 CPU 31xC and CPU 31x S7-300 - Manual (Page 120)

Technical data of CPU 31xC
6.3 CPU 313C
CPU 31xC and CPU 31x, Technical data
6-10
Manual, Edition 08/2004, A5E00105475-05
Technical data
Address areas (I/O)
Total I/O address area
max. 1024 bytes/1024 bytes
(can be freely addressed)
I/O process image 128 bytes/128 bytes
Digital channels Max. 1016
• of those local Max. 992
• Integrated channels 24 DI / 16 DO
Analog channels Max. 253
• of those local Max. 248
• Integrated channels 4 + 1 AI / 2 AO
Assembly
Racks
Max. 4
Modules per rack max. 8; max. 7 in rack 3
Number of DP masters
• Integrated None
• via CP Max. 2
Number of function modules and communication
processors you can operate
• FM Max. 8
• CP (PtP) Max. 8
• CP (LAN) Max. 6
Time-of-day
Real-time clock Yes (HW clock)
• Buffered Yes
• Buffered period Typically 6 weeks (at an ambient temperature of
40 °C)
• Behavior of the clock on expiration of the
buffered period
The clock keeps running, continuing at the time-
of-day it had when power was switched off.
• Accuracy Deviation per day < 10 s
Operating hours counter 1
• Number 0
• Value range 2 31 hours
(if SFC 101 is used)
• Granularity 1 hour
• Retentive Yes; must be manually restarted after every
restart
Clock synchronization Yes
• In the PLC Master
• On MPI Master/slave
S7 signaling functions
Number of stations that can be logged on for
signaling functions
Max. 8
(depends on the number of connections
configured for PG / OP and S7 basic
communication)