Instantaneous Residual Overcurrent Protection Efpioc (50N); Identification; Application; Setting Guidelines - ABB Relion 670 Series Applications Manual

Section 7
Current protection
7.3 Instantaneous residual overcurrent protection EFPIOC
(50N)
7.3.1

Identification

Function description
Instantaneous residual overcurrent
protection
7.3.2

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.
7.3.3

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.
GlobalBaseSel : Selects the global base value group used by the function to define ( IBase ), ( VBase )
SBase ).
and (
The setting of the function is limited to the operate residual current to the protection (
The basic requirement is to assure selectivity, that is EFPIOC (50N) shall not be allowed to operate
for faults at other objects than the protected object (line).
For a normal line in a meshed system single phase-to-ground faults and phase-to-phase-to-
ground faults shall be calculated as shown in figure
the protection are calculated. For a fault at the remote line end this fault current is I
calculation the operational state with high source impedance Z
should be used. For the fault at the home busbar this fault current is I
operational state with low source impedance Z
134
IEC 61850 IEC 60617
identification identification
EFPIOC
IN>>
IEF V1 EN-US
60 and figure 61. The residual currents (3I
and high source impedance Z
A
1MRK 511 358-UUS A
ANSI/IEEE C37.2
device number
50N
Pickup ).
. In this
fB
and low source impedance Z
A
. In this calculation the
fA
should be used.
B
Application manual
IP14508-1 v3
M14887-1 v4
M12699-3 v5
IP14985-1 v1
M12762-44 v2 M12762-4 v4
M12762-6 v7
) to
0
B