The CPU 315-2 PN/DP is a CPU with medium-sized program memory. It is used in plants containing distributed automation structures in addition to a centralized I/O. It can be implemented as a PROFINET IO controller and as a standard PROFIBUS DP master in the SIMATIC S7-300. The 315-2 PN/DP CPU can also be used as distributed intelligence (PROFIBUS DP slave or PROFINET I-Device).

The CPU 315-2 PN/DP is an ideal platform for simple software-implemented technological tasks, e.g.:

• Motion control with Easy Motion Control.
• Implementation of control engineering tasks using STEP 7 blocks or runtime software Standard PID Control/Modular PID Control.

An extended process diagnosis is possible by using SIMATIC S7-PDIAG.

The integrated communication options of the CPU enable networked automation solutions to be implemented without additional components.

CPU 315-2 PN/DP Function

• Password protection;
  a password concept protects the user program from unauthorized access.
• Block encryption;
  the functions (FCs) and function blocks (FBs) can be stored in the CPU in encrypted form by means of S7-Block Privacy to protect the know-how of the application.
• Diagnostics buffer;
  the last 500 error and interrupt events are stored in a buffer for diagnostic purposes.
• Maintenance-free data backup;
  the CPU automatically saves all data (up to 128 KB) in case of a power failure so that the data are available again unchanged when the power returns.

Parameterizable properties

The S7 configuration as well as the properties and response of the CPUs can be parameterized using STEP 7:

• General;
  definition of the name, system ID and location ID.
• Startup;
  definition of the startup characteristics of the CPU and the monitoring time
• Synchronous cycle interrupts;
  setting of DP master system, process image partition number, and delay time
• Cycle/clock memory;
  specification of the maximum cycle time and load. Setting of the clock memory address. Enabling prioritized HMI communication
• Retentivity;
  setting retentive areas
• Clock interrupts;
  setting the start date, start time and periodicity
• Watchdog interrupts;
  setting of periodicity
• System diagnostics;
  determining handling and scope of the diagnostic alarms
• Clock;
  setting the type of synchronization in the AS or on the MPI
• Protection level;
  specifying the access rights to program and data
• Communication;
  reservation of connection resources
• Web;
  settings for the Web server of the CPU
• MPI/PROFIBUS DP interface;
  setting the interface type. Determining node addresses. Parameterizing the operating mode and configuring the transfer areas in the case of PROFIBUS DP. Parameterizing the time synchronization
• PROFINET interface;
  setting of addresses. Parameterizing the PROFINET properties, the I-Device functionality, the type of synchronization on PROFINET, the time synchronization using NTP procedure, the media redundancy, and the KeepAlive function. Parameterizing port 1 and port 2

CPU 315-2 PN/DP Technical specifications

Article number		6ES7315-2EH14-0AB0
		CPU315-2 PN/DP, 384 KB
General information
HW functional status		01
Firmware version		V3.2
Engineering with
● Programming package		STEP 7 V5.5 or higher
Supply voltage
Rated value (DC)
● 24 V DC		Yes
permissible range, lower limit (DC)		20.4 V
permissible range, upper limit (DC)		28.8 V
external protection for power supply lines (recommendation)		2 A min.
Mains buffering
● Mains/voltage failure stored energy time		5 ms
● Repeat rate, min.		1 s
Input current
Current consumption (rated value)		750 mA
Current consumption (in no-load operation), typ.		150 mA
Inrush current, typ.		4 A
I²t		1 A²·s
Power loss
Power loss, typ.		4.65 W
Memory
Work memory
● integrated		384 kbyte
● expandable		No
● Size of retentive memory for retentive data blocks		128 kbyte
Load memory
● Plug-in (MMC)		Yes
● Plug-in (MMC), max.		8 Mbyte
● Data management on MMC (after last programming), min.		10 y
Backup
● present		Yes; Guaranteed by MMC (maintenance-free)
● without battery		Yes; Program and data
CPU processing times
for bit operations, typ.		0.05 µs
for word operations, typ.		0.09 µs
for fixed point arithmetic, typ.		0.12 µs
for floating point arithmetic, typ.		0.45 µs
CPU-blocks
Number of blocks (total)		1 024; (DBs, FCs, FBs); the maximum number of loadable blocks can be reduced by the MMC used.
DB
● Number, max.		1 024; Number range: 1 to 16000
● Size, max.		64 kbyte
FB
● Number, max.		1 024; Number range: 0 to 7999
● Size, max.		64 kbyte
FC
● Number, max.		1 024; Number range: 0 to 7999
● Size, max.		64 kbyte
OB
● Size, max.		64 kbyte
● Number of free cycle OBs		1; OB 1
● Number of time alarm OBs		1; OB 10
● Number of delay alarm OBs		2; OB 20, 21
● Number of cyclic interrupt OBs		4; OB 32, 33, 34, 35
● Number of process alarm OBs		1; OB 40
● Number of DPV1 alarm OBs		3; OB 55, 56, 57
● Number of isochronous mode OBs		1; OB 61
● Number of startup OBs		1; OB 100
● Number of asynchronous error OBs		6; OB 80, 82, 83, 85, 86, 87 (OB83 only for PROFINET IO)
● Number of synchronous error OBs		2; OB 121, 122
Nesting depth
● per priority class		16
● additional within an error OB		4
Counters, timers and their retentivity
S7 counter
● Number		256
Retentivity
— adjustable		Yes
— lower limit		0
— upper limit		255
— preset		Z 0 to Z 7
Counting range
— can be set		Yes
— lower limit		0
— upper limit		999