Instantaneous Residual Overcurrent Protection Efpioc (50N) - ABB RELION 670 SERIES Applications Manual

Section 9
Current protection
9.3
9.3.1
9.3.2
9.3.3
504
D ³ + +
t 40 ms 100 ms
EQUATION1266 V1 EN
where it is considered that:
the operate time of overcurrent protection B1 is 40 ms
the breaker open time
the resetting time of protection A1
the additional margin
Instantaneous residual overcurrent protection EFPIOC
(50N)
Identification
Function description
Instantaneous residual overcurrent
protection
Application
In many applications, when fault current is limited to a defined value by the object
impedance, an instantaneous ground-fault protection can provide fast and selective
tripping.
The Instantaneous residual overcurrent EFPIOC (50N), which can operate in 15 ms (50
Hz nominal system frequency) for faults characterized by very high currents, is included
in the IED.
Setting guidelines
The parameters for the Instantaneous residual overcurrent protection EFPIOC (50N) are
set via the local HMI or PCM600.
Some guidelines for the choice of setting parameter for EFPIOC (50N) is given.
+ =
40 ms 40 ms 220 ms
is 100 ms
is 40 ms and
is 40 ms
IEC 61850
identification
EFPIOC
1MRK 506 369-UUS -
IEC 60617 ANSI/IEEE C37.2
identification device number
50N
IN>>
IEF V1 EN
Line distance protection REL670 2.2 ANSI
Application manual
(Equation 454)