Siemens siprotec 7SA6, Manual

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Functions
6-81
7SA6 Manual
C53000-G1176-C156-2
If the communication is interrupted for a permanent period (which is longer than a set-
table time period), this can be regarded as a transmission failure. A corresponding
alarm is output. Otherwise the same reactions apply as for the data disturbance.
6.4.2 Setting Function Parameters
General
Information on
Protection Data
Interfaces The protection data interfaces connect the devices with the communication media.
The communication is permanently monitored by the devices. Address
4509 T-DATA
DISTURB
defines after which delay time the user is informed about a faulty or missing
telegram. Address
4510 T-DATAFAIL
is used to set the time after which a
transmission failure alarm is output.
Protection Data
Interface 1 The protection data interface 1 can be switched
on
or
off
with address
4501 STATE
PROT I 1
. If it is switched
off
, this can be regarded as a transmission failure. In case
of a ring topology the transmission of data can continue their operation, but not in case
of a chain topology.
Address
4502 CONNEC. 1 OVER
to set the transmission media that you want to
connect to protection data interface PROT I 1. The following media are possible
F. optic direct
, i.e. communication directly by fibre-optic cable, communication
with 512 kBit/s,
Com conv 64 kB
, i.e. via communication converters with 64 kBit/s (G703, 1 or X21)
Com conv 128 kB
, i.e. via communication converters 128 kBit/s (X21)
Com conv 512 kB
, i.e. via communication converters 512 kBit/s (X21).
The options for the different device versions may vary. The data must be identical at
both ends of a communication route.
The setting depends on the features of the communication media. As a general rule,
it can be said that the higher the transmission rate, the shorter the response time of
the teleprotection scheme.
The devices measure and monitor the transmission times. Deviations are corrected,
as long as they are within the permissible range. These permissible ranges are set
under addresses 4505A and 4506A and can normally be left at their default setting.
The maximum permissible delay time (address 4505A
PROT 1 T-DELAY
) is set to a
value that does not exceed the usual value of communication media. This parameter
can only be changed with DIGSI
®
4 under “Additional Settings“. If it is exceeded (e.g.
when a different way of transmission is used), the message “
PI1 TT alarm
” is
issued.
Communication
Topology
First of all, define your communication topology: number the devices consecutively.
This numbering is a serial device index that serves for your own overview. It starts for
each Distance Protection system (i.e. for each protected object) with 1. For the
Distance 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. As a result the time
information of all devices is comparable at all times. The device index is to exactly
determine the devices of the Distance Protection (i.e. for a protective relay).
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