Specification; Function Diagrams - Siemens SINAMICS Series Operating Instructions Manual

10.9 Serial interface with USS protocol

Specification

Developed by Siemens, the USS® protocol is a proprietary fieldbus which was already being
used in a variety of applications before PROFIBUS was established.
The USS® protocol is described in the following document:
USS® Protocol Specification: Order number E20125-D0001-S302-A1
Properties
The USS® protocol can only be used as a fieldbus instead of PROFIBUS; USS and
PROFIBUS cannot run at the same time.
The USS® protocol enables one or more SINAMICS DCMs to be connected to a master
station. It is a point-to-point coupling or a bus-type coupling. A maximum of 31 nodes can be
connected in the bus configuration (1 master and a maximum of 30 slaves). The bus
terminator must be activated on both bus nodes at each end of the bus line.
The USS® protocol enables access to all relevant process data, diagnostic information, and
parameters for the SINAMICS DCM.
The USS® protocol is purely a master-slave protocol in which a SINAMICS DCM can only
ever be a slave. In this case, a SINAMICS DCM only sends a telegram to the master if it has
received a telegram from it. Therefore, SINAMICS DCMs cannot use the USS® protocol to
exchange data with one another directly.
Connecting
Terminal X178, X179

Function diagrams

The function diagrams for the fieldbus interface are relevant:
See FP2410, FP2420, FP2440, FP2442, FP2450, FP2452, FP2460, FP2470, FP2472,
FP2481, and FP2483.
SINAMICS DCM DC Converter
Operating Instructions, 12/2018, A5E34763375A
Descriptions of functions
10.9 Serial interface with USS protocol
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