Siemens Simatic S7 Series System Manual

Communication
8.6 RS485
S7-200 SMART
396 System Manual, 09/2015, A5E03822230-AC
PPI protocol and S7-200 SMART CPUs
PPI Advanced allows network devices to establish a logical connection between the devices.
With PPI Advanced, there are a limited number of connections supplied by each device. See
the following table for the number of connections supported by the S7-200 SMART CPU.
All S7-200 SMART CPUs support both PPI and PPI Advanced protocols.
Table 8- 13 Number of connections for the S7-200 SMART CPU
Module
Baud rate
Connections
RS485 port
9.6 kbaud, 19.2 kbaud, or 187.5 kbaud
4
RS485/RS232 signal board 9.6 kbaud, 19.2 kbaud, or 187.5 kbaud 4
8.6.2
Baud rate and network address
8.6.2.1
Definition of baud rate and network address
Baud rate
The speed that data is transmitted across the network is the baud rate, which is typically
measured in units of kilobaud (kbaud) or megabaud (Mbaud). The baud rate measures how
much data can be transmitted within a given amount of time. For example, a baud rate of
19.2 kbaud describes a transmission rate of 19,200 bits per second.
Every device that communicates over a given network must be configured to transmit data at
the same baud rate. Therefore, the fastest baud rate for the network is determined by the
slowest device connected to the network.
The following table lists the baud rates supported by the S7-200 SMART CPU.
Table 8- 14 Baud rate supported by the S7-200 SMART CPU
Network
Baud rate
PPI protocol
9.6 kbaud, 19.2 kbaud, and 187.5 kbaud only
Freeport Mode 1200 baud to 115.2 kbaud

Siemens Simatic S7 Series Specifications

General

CPU	Varies by model (e.g., S7-300, S7-400, S7-1200, S7-1500)
Communication Interfaces	PROFIBUS, PROFINET, Ethernet, MPI
Programming	TIA Portal, STEP 7
Programming Languages	LAD, FBD, STL, SCL, GRAPH
I/O Modules	Digital, Analog, Specialty modules available
Operating Temperature	0°C to 60°C (standard models)
Mounting	DIN rail mounting
Operating Voltage	24V DC or 120/230V AC (varies by model)
Protection Class	IP20 (standard models)
Memory	Varies depending on the S7 model. Includes work memory (RAM) for program execution, load memory (EEPROM or Flash) for program storage, and system memory for operating system functions. Memory sizes range from kilobytes to megabytes.