ABB REB670 Series - Four step single phase overcurrent protection PH4 SPTOC; Identification; Application

40 100 40 40 220t ms ms ms ms msD ³ + + + =
EQUATION1266 V1 EN-US (Equation 29)
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 Four step single phase overcurrent protection
PH4SPTOC
SEMOD127812-1 v2
7.2.1 Identification
SEMOD127810-2 v2
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Four step single phase overcurrent
protection
PH4SPTOC
4
4
alt
I>
OC V1 EN-US
51
7.2.2 Application
SEMOD127937-4 v2
The Four step single phase overcurrent protection(PH4SPTOC) function is used in several
applications in the power system. Some applications are:
• Short circuit protection of feeders in distribution and subtransmission systems. Normally
these feeders have radial structure.
• Back-up short circuit protection of transmission lines.
• Back-up short circuit protection of power transformers
• Short circuit protection of different kinds of equipment connected to the power system
such as; shunt capacitor banks, shunt reactors, motors and others.
• Back-up short circuit protection of power generators.
The single phase overcurrent protection is used in IEDs having only input from one phase, for
example busbar protection for large busbars (with many bays).
In many applications several steps with different current pick up levels and time delays are
needed. PH4SPTOCcan have up to four different, individual settable, steps. The flexibility of
each step of PH4SPTOC function is great. The following options are possible:
Choice of delay time characteristics: There are several types of time delay characteristics
available such as definite time delay and different types of inverse time delay characteristics.
The selectivity between different overcurrent protections is normally enabled by co-ordination
between the function time delays of the different protections. To enable optimal co-ordination
all overcurrent IEDs, to be co-ordinated against each other, should have the same time delay
characteristic. Therefore a wide range of standardised inverse time characteristics are
Section 7 1MRK 505 370-UEN D
Current protection
152 Busbar protection REB670
Application manual