Siemens 7SJ82, Manual

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[dwinterf-030211-01.tif, 1, en_US]
Figure 3-39 Data Exchange for 2 Devices, Each Having Protection Communication
i
i
NOTE
The index describes the consecutive numbering of the devices in a protection topology (see parameter
Local device is device
).
A maximum of 2 protection communications can be integrated in one device (see next figure). If 2 protection
communications of the same type are connected to one another, this results in 100 % redundancy regarding
the transmission route. The devices then search for the communication connection with the highest band-
width (for example, optical fiber). If this connection fails, the system switches over automatically to the 2nd
connection until the 1st connection is available again. As the connection with lower bandwidth defines the
maximum amount of transferable information, the same information is exchanged via both connections. Both
protection communications in the device are then of type 1.
[dwintera-030211-02.tif, 1, en_US]
Figure 3-40 Data Exchange for 2 Devices, Each Having 2 Protection Communications/Redundant Transmis-
sion Route
Protection-Interface Information Transfer
With the protection-interface information transfer, customer-specific indications and measured values can be
communicated via the protection interface with settable update cycles (priorities).
There are 3 different priorities when transferring protection-interface information:
•
Priority 1: Use Priority 1 for the transmission of fast protection signals that are transferred and updated
at a maximum of every 20 ms in a telegram.
•
Priority 2: Use Priority 2 for the transmission of fast single-point or double-point indications that are
transferred and updated at a maximum of every 40 ms.
•
Priority 3: Use Priority 3 for all indications, measured, and metered values that are transferred and
updated a maximum of every 100 ms.
The number of customer-specific signals, indications, and measured values conform with the remaining band-
width. The remaining bandwidth is lower than with all other protection functions (type 2) when using a differ-
ential protection (type 1). Customer-specific measured values consume more bandwidth than single-point
indications.
Communication Media
The communication takes place via direct fiber-optic connections, via communication networks or via 2-wire
copper conductors. Siemens recommends a direct fiber-optic connection, as this offers the highest transmis-
sion rate of 2 MBit/s and is immune to failures in the communication route while offering the shortest trans-
System Functions
3.5 Protection Communication
114 SIPROTEC 5, Overcurrent Protection, Manual
C53000-G5040-C017-8, Edition 07.2017