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113
Scheme communication logic for residual
overcurrent protection (EFC)
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This communication logic is intended for residual overcurrent protections.
To achieve fast fault clearing for a fault on the part of the line not covered by the instan-
taneous zone 1, the directional residual overcurrent protection function can be support-
ed with logic, that uses communication channels.
One communication channel in each direction, which can transmit an on/off signal is
required. The performance and security of this function is directly related to the trans-
mission channel speed and security against false or lost signals. So special channels are
used for this purpose. When power line carrier is used for communication, these special
channels are strongly recommended due to the communication disturbance caused by
the primary fault.
In the directional comparison scheme, information of the fault current direction must be
transmitted to the other line end.
With directional comparison, an operate time of 50-60 ms, including a channel trans-
mission time of 20 ms, can be achieved. This short operate time enables rapid automatic
reclosing function after the fault.
During a single-phase reclosing cycle, the auto-reclosing device must block the direc-
tional comparison earth-fault scheme.
The communication logic module for the REx 5xx terminal contains circuits for block-
ing overreach and permissive overreach schemes.
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The directional comparison function contains logic for blocking overreach and permis-
sive overreach schemes.
Use the independent or inverse time functions in the directional earth-fault protection
module to get back-up tripping in case the communication equipment malfunctions that
prevents operation of the directional comparison logic.
Содержание REO 517
Страница 10: ... RQWHQWV ...
Страница 16: ...6 Introduction to the application manual KDSWHU QWURGXFWLRQ ...
Страница 64: ...54 Blocking of signals during test KDSWHU RPPRQ IXQFWLRQV ...
Страница 88: ...78 Scheme communication logic ZCOM KDSWHU LQH LPSHGDQFH ...
Страница 100: ...90 Time delayed phase and residual overcurrent protection TOC1 KDSWHU XUUHQW Equation 36 Iset IsSEC I1b 100 ...
Страница 146: ...136 Unbalance protection for capacitor banks TOCC KDSWHU XUUHQW ...
Страница 166: ...156 Dead line detection DLD KDSWHU 3RZHU V VWHP VXSHUYLVLRQ ...
Страница 171: ...161 About this chapter KDSWHU RQWURO KDSWHU RQWURO ERXW WKLV FKDSWHU This chapter describes the control functions ...
Страница 293: ...283 About this chapter KDSWHU RJLF KDSWHU RJLF ERXW WKLV FKDSWHU This chapter describes the logic functions ...
Страница 378: ...368 Monitoring of DC analog measurements KDSWHU 0RQLWRULQJ ...
Страница 379: ...369 About this chapter KDSWHU 0HWHULQJ KDSWHU 0HWHULQJ ERXW WKLV FKDSWHU This chapter describes the metering functions ...
Страница 384: ...374 Pulse counter logic PC KDSWHU 0HWHULQJ ...
Страница 412: ...402 Serial communication modules SCM KDSWHU DWD FRPPXQLFDWLRQ ...
Страница 440: ...430 LED indication module KDSWHU DUGZDUH PRGXOHV ...