Additional Security Logic For Differential Protection Ldrgfc (11); Identification; Application - ABB RELION 670 SERIES Applications Manual

Section 7
Differential protection
IEC05000749 V1 EN
Figure 55: Current voltage characteristics for the non-linear resistors, in the range 10-200 V, the average range
of current is: 0.01–10 mA
7.2
7.2.1
7.2.2
152
Additional security logic for differential protection
LDRGFC (11)

Identification

Function description
Additional security logic for differential
protection

Application

Additional security logic for differential protection LDRGFC (11) can help the security of
the protection especially when the communication system is in abnormal status or for
example when there is unspecified asymmetry in the communication link. It reduces the
probability for mal-operation of the protection. LDRGFC (11) is more sensitive than the
main protection logic to always release operation for all faults detected by the differential
function. LDRGFC (11) consists of four sub functions:
IEC 61850 IEC 60617
identification identification
LDRGFC -
Line distance protection REL670 2.2 ANSI
1MRK 506 369-UUS -
ANSI/IEEE C37.2
device number
11
Application manual