Siemens SINAUT ST7 System Manual page 286

Glossary
situation when information with higher priority needs to be sent or when the partner
establishes a connection to exchange data.
Squelch
Squelch
Squelch reduces the interfering noise in communications during breaks in transmission. This
increases the signal-to-noise ratio.
ST7 message
ST7 messages consist of a frame, an area for addresses and control fields (message
header) and an area for net data (object data) with the time stamp. The ST7 messages are
divided into organizational messages and data messages. The structure of an ST7 message
is based on the guidelines of the ST7 protocol.
ST7 protocol
This protocol is used in the SINAUT ST7 system for transmitting process data over WANs.
ST7cc
SINAUT ST7cc is the ideal control center system based on SIMATIC WinCC for SINAUT
ST7.
It is specially designed for event-driven and time-stamped data transmission in the SINAUT
system. It avoids the possible loss of data that can occur with cyclic polling in WinCC. It also
ensures the use of the correct event time supplied by the SINAUT stations for all WinCC
messages and archive entries. The integrated process image contains all process data as
well as the status of all SINAUT subscribers in the network and makes this data available
directly to WinCC for fast transfer to the process image.
ST7sc
The SINAUT system allows the networking of SIMATIC stations with a control center over a
WAN (Wide Area Network). This control center can also be a SIMATIC station or a PC-
based control center, for example, WinCC with the SINAUT ST7cc add-on.
SINAUT ST7sc allows the manufacturers of control systems to connect to SINAUT without
needing to integrate a SINAUT interface. Communication is over OPC: As an OPC server,
SINAUT ST7sc forms the interface between the SINAUT system and a control system
connected as an OPC client.
The OPC interface is also suitable for data exchange with other applications, for example,
the Microsoft Office application Excel.
Station
In the SINAUT world, the term station includes the entire hardware components required for
acquisition, processing and communication with other stations or a master station. A station
can, for example, consist of a modem, a TIM and a programmable controller (in turn
consisting of a CPU and I/O modules). A SINAUT station can also include several
programmable controllers, or, in the case of a node station, several TIMs.
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System Manual, 07/2009, C79000-G8976-C178-07
Station control system