Siemens SINAMICS Series Operating Instructions Manual page 540

Descriptions of functions
10.8 Communication via Modbus TCP
10.8 Communication via Modbus TCP
10.8.1 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 DCM.
Modbus functionality
Process data and parameters are accessed via the Modbus register.
● Process data: 40100 - 40119
A maximum of 10 process data (PZD) can be exchanged.
● 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 STARTER/Startdrive with S7 protocol
● DCP (Discovery and Configuration Protocol) to set the IP address etc.
● SNMP for identification
General information about communication
Communication with Modbus TCP uses the Ethernet/PROFINET interface:
X1400:
For Modbus TCP with a CUD via a CBE20.
The following applies for the CUD:
● An advanced CUD must be inserted.
● The memory card (with the device firmware) must be inserted.
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SINAMICS DCM DC Converter
Operating Instructions, 12/2018, A5E34763375A