Identification; Functionality - ABB RET650 Technical Manual

1MRK 504 135-UEN A
8.4.1
8.4.2
Technical manual

Identification

Function description
Four step residual overcurrent
protection, zero or negative sequence
direction

Functionality

The four step residual overcurrent protection, zero or negative sequence direction
(EF4PTOC) has a settable inverse or definite time delay independent for step 1 and 4
separately. Step 2 and 3 are always definite time delayed.
All IEC and ANSI inverse time characteristics are available.
EF4PTOC can be set directional or non-directional independently for each of the
steps.
The directional part of the function can be set to operate on following combinations:
• Directional current (I3PDir) versus Polarizing voltage (U3PPol)
• Directional current (I3PDir) versus Polarizing current (I3PPol)
• Directional current (I3PDir) versus Dual polarizing (UPol+ZPol x IPol) where
ZPol = RPol + jXPol
IDir, UPol and IPol can be independently selected to be either zero sequence or
negative sequence.
Other setting combinations are possible, but not recommended.
Second harmonic blocking level can be set for the function and can be used to block
each step individually.
Current protection
IEC 61850 IEC 60617
identification identification
EF4PTOC
2
IEC11000263 V1 EN
Section 8
ANSI/IEEE C37.2
device number
51N/67N
155