Siemens siprotec 7SA522, User Manual

Page: 278 / 628

Functions
6-130
7SA522 Manual
C53000-G1176-C119-2
6.8 External Direct and Remote Tripping
6.8.1 Method of Operation
External Trip of the
Local Circuit
Breaker Any signal from an external protection or monitoring device can be coupled into the
signal processing of the 7SA522 by means of a binary input. This signal may be de-
layed, alarmed and routed to one or several output relays. A reset delay can also be
set to ensure reliable switching of the circuit breaker even if the initiating signal is a
very short impulse. In Figure 6-76 the logic diagram is shown. If the device and circuit
breaker are capable of single-phase operation, it is also possible to trip single phase.
The tripping logic of the device in this case ensure that the conditions for single-phase
tripping are satisfied (e.g. single-phase tripping enabled, automatic reclosure ready).
The external tripping can be switched on and off with a setting parameter and may be
blocked via binary input.
Figure 6-76 Logic diagram of the local external tripping
Remote Trip of the
Circuit Breaker at
the Opposite Line
End For remote tripping at the opposite line end, one separate communication channel is
required for each required transmission direction. For this purpose, fibre-optic commu-
nication channels could for example be used or communication cables with voice fre-
quency modulated HF channels, power line carrier or microwave radio channels.
If the trip command of the distance protection is to be transmitted, it is best to use the
integrated teleprotection function for the transmission of the signal as this already in-
corporates the optional extension of the transmitted signal, as described in Sub-sec-
tion 6.4.1.2. Any of the commands can of course be used to trigger the transmitter to
initiate the send signal.
On the receiver side, the local external trip function is used. The receive signal is rout-
ed to a binary input which is assigned to the logical binary input function “
!'777ULS
/
”. If single pole tripping is required, the following binary inputs may alternatively
be used “
!'777ULS/
”, “
!'777ULS/
” and “
!'777ULS/
”. Figure 6-76 there-
fore also applies in this case.
4417
≥
1
7ULS7LPH'(/$<
0 T
≥
1
&
≥
1
0 T
≥
1
0 T
&
&
ON
OFF
'77'LUHFW7ULS
„1“
Tripping logic
&
>DTT Trip L123
4412 >DTT Trip L1
4413 >DTT Trip L2
4414 >DTT Trip L3
4403 >BLOCK DTT
4432 DTT TRIP 1p. L1
4433 DTT TRIP 1p. L2
4434 DTT TRIP 1p. L3
4435 DTT TRIP L123
4421 DTT OFF
4422 DTT BLOCK