Communicate with S7-300 via Ethernet

1.   General

WECON PI Series HMI can communicate with SIEMENS PLC via Ethernet port. So far, S7-300 and S7-1200 are supported.

2.   Address list

There are some difference between HMI address list and PLC real address, this sector introduce the difference between HMI and PLC address.

Table 2‑1

Type Register in HMI Register in PLC Format Range Note
Word address MB M MBn 0~99999
MW M MWn 0~99999


MW0 = MB0-1 MW2 = MB2-3

Using the even address

MD M MDn 0~99999


MD0 = MB0-3 MD4 = MB4-7
IW I  IWn 0~99999
QW Q QWn 0~99999
DBxDBB DB0.DB-DB99.DB DBxDBBnnxxxx 000000~999999 DB10DBB1=DBxDBB100001
DBxDBW DB0.DB-DB99.DB DBxDBWnnxxxx 000000~999999 DB10DBW1=DBxDBW100001
DBxDBD DB0.DB-DB99.DB DBxDBDnnxxxx 000000~999999 DB10DBD1=DBxDBD100001
Bit address I  I Mn.x 0.0~99999.7
Q  Q Qn.x 0.0~99999.7
M M Mn.x 0.0~99999.7
DBxDB DB0.DB-DB99.DB DBxDBnnxxxx.y 000000.0~999999.7 DB10DB1.1=DBxDB100001.1


3.   Communication parameters

This sector introduces the setting for communication parameters.

3.1 Protocol

Select the communication protocol when create a new project as Figure 1 shows. Or change the communication protocol for an existing project by click [Project] menu, and select [Communication] in [Settings] toolbar, and click [Setting] to open the protocol list, as Figure 2 shows.


Figure 1


Figure 2

3.2 Communication parameters

Different from the communication by Serial port, it requires set device IP for communication. So please click the [Setting] button in [Device IP] option, and it will pop-up [TCP/IP parameters] as Figure 3 shows.


Figure 3

  • PLC IP Address: It is used for entering the PLC IP address;
  • PLC Port No.: It is used for entering PLC port Number;
  • Network: It is used for selecting type;

Note:The default setting in PLC of PLC port No. is 102, and the default Network type is [TCP_Client_2N]. But please make sure the setting is same as PLC’s in real situation.








Version: V1.0.0

Date: Dec 2016