Protection Data Interfaces And Protection Data Topology; Functional Description; Protection Data Topology / Protection Data Communication - Siemens SIPROTEC Manual

Functions

2.2 Protection Data Interfaces and Protection Data Topology

2.2 Protection Data Interfaces and Protection Data Topology
As described in the explanation of the function principle of the differential protection (see Section 2.3), the
devices protecting a protected object have to exchange the data of the protected object. This applies not only
to the measured quantities relevant to the actual differential protection, but also to all data which are to be avail-
able at the ends. These data include also the synchronisation and topological data as well as the intertripping,
transfer trip, remote annunciation signals and measured values. The topology of the protected object, the allo-
cation of the devices to the ends of the protected object and the allocation of the communication paths to the
protection data interfaces of the devices form the topology of the protection system and its communication.
2.2.1

Functional Description

2.2.1.1 Protection Data Topology / Protection Data Communication

Protection Data Topology
For a standard layout of lines with two ends, you require one protection data interface for each device. The
protection data interface is named PI 1 (see also Figure 2-7). When configuring the functional scope (Section
2.1.1), the corresponding protection data interface must have been configured as Enabled.
With 7SD5 it is also possible to connect both protection data interfaces to each other provided that the two
devices have two protection data interfaces each and that the relevant transmission media are available. This
provides for 100% redundancy as far as the transmission is concerned (Figure 2-8). The devices then search
autonomously for the fastest communication link. If this link fails, the devices automatically switch to the other
link until the faster link is available again..
Figure 2-7
Figure 2-8
74
Differential protection for two ends with two 7SD5 devices, each of them having one protection
data interface (transmitter/receiver)
Differential protection for two ends with two 7SD5 each of them having two protection data
interfaces (transmitter/receiver)
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011