Functions
2.11 Measures for Weak and Zero Infeed
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011
278
An endless echo signal between the line ends is avoided (e.g. interference coupling in the signal path) by block-
ing a new echo for a certain time
Echo BLOCK Time
(address
2504
) after each output of an echo signal.
Typical setting is approx. 50ms. In addition, the echo is also blocked for the time
Echo BLOCK Time
after the
distance protection or earth fault protection signal was sent. This parameter can only be altered with DIGSI
under
Additional Settings
.
In applications with one common transmission channel used by both the distance and the earth fault protection
spurious trippings may occur if distance protection and earth fault protection create an echo independently of
each other. In this case the parameter
Echo:1channel
(address
2509
) has to be set to
YES
. The presetting
is
NO
.
Note
The
„ECHO SIGNAL“
(No. 4246) must be separately allocated to the output relay for the transmitter actuation
as it is not included in the transmit signals of the transmission functions.
2.11.3
Tripping According to French Specification
2.11.3.1 Functional Description
An alternative for detecting weak infeed is only available in the models 7SD5***-**D**.
Pickup with Relative Voltage Jump
In addition to the classical function of weak infeed, the so called
Logic no. 2
(address
125
) presents an
alternative to the method used so far.
This function operates independently of the teleprotection scheme by using its own receive signal and it is able
to trip with delay and without delay.
Содержание SIPROTEC
Страница 20: ...Contents SIPROTEC 7SD5 Manual C53000 G1176 C169 5 Release date 02 2011 20 ...
Страница 351: ...Functions 2 18 Synchronism and Voltage Check optional SIPROTEC 7SD5 Manual C53000 G1176 C169 5 Release date 02 2011 351 ...
Страница 494: ...Functions 2 27 Command Processing SIPROTEC 7SD5 Manual C53000 G1176 C169 5 Release date 02 2011 494 ...
Страница 640: ...Technical Data 4 27 Dimensions SIPROTEC 7SD5 Manual C53000 G1176 C169 5 Release date 02 2011 640 ...
Страница 657: ...Appendix A 2 Terminal Assignments SIPROTEC 7SD5 Manual C53000 G1176 C169 5 Release date 02 2011 657 7SD5 W ...
Страница 754: ...Appendix A 10 Measured Values SIPROTEC 7SD5 Manual C53000 G1176 C169 5 Release date 02 2011 754 ...
Страница 756: ...Literature SIPROTEC 7SD5 Manual C53000 G1176 C169 5 Release date 02 2011 756 ...
Страница 768: ...Glossary SIPROTEC 7SD5 Manual C53000 G1176 C169 5 Release date 02 2011 768 ...