Overview - Siemens SINAMICS S120 Series Function Manual

Communication via Modbus TCP
6.1

Overview

The Modbus protocol is a communication protocol based on a controller/device architecture.
Modbus offers three transmission modes:
● Modbus ASCII - via a serial interface
data in the ASCII code. The data throughput is lower compared to RTU.
● Modbus RTU - via a serial interface
data in the binary format. The data throughput is greater than in ASCII code.
● Modbus TCP - via Ethernet
data as TCP/IP packages. TCP port 502 is reserved for Modbus TCP.
Only transfer type "Modbus TCP" is available for SINAMICS S120.
Possible drive units:
● CU320-2 PN
● CU320-2 DP (CBE20)
● CU310-2 PN
Modbus functionality
Process data and parameters are accessed via the Modbus register.
● Process data: 40100 - 40119
● Drive data: 40300 - 40522
● All parameters via DS47: 40601 - 40722
Modbus TCP always provides a basic Ethernet functionality, which corresponds to the
functionality of Ethernet interface X127:
● Commissioning access for Startdrive with the S7 protocol
● DCP to set the IP address etc.
● SNMP for identification
Communication
Function Manual, 12/2018, 6SL3097-5BD00-0BP0
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