Siemens S7-300 appendix Technical data

Technical data of CPU 31x 7.7 CPU 317-2 PN/DP

Technical data

IEC Timers		Yes
•	Type	SFB
•	Number	Unlimited
		(limited only by RAM size)
Data areas and their retentivity
Flag bits		4096 bytes
•	Retentive memory	Configurable
•	Default retentivity	From MB0 to MB15
Clock flag bits		8 (1 byte per flag bit)
Data blocks
•	Number	2047
		(DB 1 to DB 2047)
•	Length	64 KB
• Non-Retain support (configured retention)		Yes
Local data per priority class		max. 1024 bytes
Blocks
Total		2048 (DBs, FCs, FBs)
		The maximum number of blocks that can be
		loaded may be reduced if you are using another
		MMC.
OBs		See the Instruction List
•	Length	64 KB
Nesting depth
•	Per priority class	16
• additional within an error OB		4
FBs		See the Instruction List
•	Number	2048
		(FB 0 to FB 2047)
•	Length	64 KB
FCs		See the Instruction List
•	Number	2048
		(FC 0 to FC 2047)
•	Length	64 KB
Address areas (I/O)
Total I/O address area		max. 8192 bytes/8192 bytes
		(can be freely addressed)
Distributed		max. 8192 bytes
I/O process image
•	Configurable	2048/2048
•	Default	256/256
Digital channels		65536/65536
of those local		Max. 1024

7-34	CPU 31xC and CPU 31x, Technical data
	Manual, Edition 08/2004, A5E00105475-05