ABB REB650 - Directional Residual Overcurrent Protection, Four Steps EF4 PTOC; Identification; Application

40 100 40 40 220t ms ms ms ms msD ³ + + + =
EQUATION1266 V1 EN-US (Equation 24)
where it is considered that:
the operate time of overcurrent protection B1 is 40 ms
the breaker open time is 100 ms
the resetting time of protection A1 is 40 ms and
the additional margin is 40 ms
7.2 Directional residual overcurrent protection, four
steps EF4PTOC
IP14509-1 v8
7.2.1 Identification
M14881-1 v6
Function description
IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Directional residual overcurrent
protection, four steps
EF4PTOC
4(IN>)
4
alt
4
TEF-REVA V2 EN-US
51N_67N
7.2.2 Application
M12509-12 v10
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:
Section 7 1MRK 505 388-UEN B
Current protection
102 Busbar protection REB650 2.2 IEC
Application manual