ABB Relion 670 Series Applications Manual page 149

1MRK 511 401-UEN Rev. K
8.4 Directional residual overcurrent protection, four steps
EF4PTOC
8.4.1 Function revision history
Document
revision
A
B
C
D
E
F
G
H
8.4.2 Identification
Function description
Directional residual overcurrent
protection, four steps
8.4.3 Application
The directional residual overcurrent protection, four steps EF4PTOC is used in several
applications in the power system. Some applications are:
• Earth-fault protection of feeders in effectively earthed distribution and subtransmission
systems. Normally these feeders have radial structure.
• Back-up earth-fault protection of transmission lines.
• Sensitive earth-fault protection of transmission lines. EF4PTOC can have better sensitivity
to detect resistive phase-to-earth-faults compared to distance protection.
• Back-up earth-fault protection of power transformers.
• Earth-fault protection of different kinds of equipment connected to the power system
such as shunt capacitor banks, shunt reactors and others.
In many applications, several steps with different current operating levels and time delays are
needed. EF4PTOC can have up to four, individual settable steps. The flexibility of each step of
EF4PTOC is great. The following options are possible:
Non-directional/Directional function: In some applications the non-directional functionality is
used. This is mostly the case when no fault current can be fed from the protected object itself.
In order to achieve both selectivity and fast fault clearance, the directional function can be
necessary. This can be the case for earth-fault protection in meshed and effectively earthed
Bay control REC670
Application manual
Product History
revision
2.2.1 -
2.2.1 -
2.2.2 Technical data table updated with note "Operate time and reset time are only valid
if harmonic blocking is turned off for a step".
2.2.3 -
2.2.3 -
2.2.3 -
2.2.4 -
2.2.4 The phase selection logic is added to allow phase segregated trip. The new phase
selections outputs added to this release are PHSELL1, PHSELL2 and PHSELL3. The
setting EnPhaseSel is added to enable or disable phase selection. The maximum
value changed to 2000.0 % of IBase for
IEC 61850
identification
EF4PTOC
© Copyright 2017 Hitachi Power Grids. All rights reserved
GUID-0F9199B0-3F86-45E0-AFC2-747052A20AE1 v1
IMin1, IMin2, IMin3 and IMin4 settings.
IEC 60617 ANSI/IEEE C37.2
identification device number
51N_67N
4(IN>)
4
alt
4
TEF-REVA V2 EN-US
Section 8
Current protection
IP14509-1 v8
M14881-1 v7
M12509-12 v11
143