Differential Protection Topology; Setting Notes - Siemens siprotec 7SD5 User Manual

2.2.3

Differential Protection Topology

2.2.3.1

Setting Notes

Protection Data First of all, define your protection data communication topology: number the devices
Topology consecutively. This numbering is a serial device index that serves for your own over-
view. It starts for each distance differential protection system (i.e. for each protected
object) with 1. For the differential protection system the device with index 1 is always
the absolute-chronology master, i.e. the absolute time management of all devices
which belong together depends on the absolute time management of this device, if
synchronization is set to Timing-Master. As a result the time information of all devices
is comparable at all times. The device index serves for unique definition of the devices
within the differential protection system (i.e. for one protected object).
An ID number is also to be given to each single device (device-ID). The device–ID is
used by the communication system to identify each individual device. It must be
between 1 and 65534 and must be unique within the communication system. The ID
number identifies the devices in the communication system (like a device address)
since the exchange of information between several differential protection systems
(thus also for several protective relay) can be executed via the same communication
system.
Please make sure that the possible communication links and the existing interfaces
are in accordance with each other. If not all devices are equipped with two protection
data interfaces, those with only one protection data interface must be located at the
ends of the communication chain. A ring topology is only possible if all devices in a
differential protection system are equipped with two protection data interfaces.
If you work with different physical interfaces and communications links, please make
sure that every protection data interface corresponds to the projected communication
link.
For a protected object with two ends (e.g. a line) the addresses 4701 ID OF RELAY
1 and 4702 ID OF RELAY 2 are set, e.g. for device 1 the device-ID 16 and for device
2 the device-ID 17 (Figure 2-12). The indices of the devices and the device-IDs do not
have to match here, as mentioned above.
Figure 2-12
7SD5 Manual
C53000-G1176-C169-1
2.2 Protection Data Interfaces and Protection Data Topology
Differential protection topology for 2 ends with 2 devices — example
85