Function Block - ABB REL650 series Technical Manual

Section 7
Current protection
7.6.3
7.6.4
216
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.
EF4PTOC (51N/67N) can be used as main protection for phase-to-ground faults.
EF4PTOC (51N/67N) can also be used to provide a system back-up for example, in the
case of the primary protection being out of service due to communication or voltage
transformer circuit failure.
Directional operation can be combined together with corresponding communication logic
in permissive or blocking teleprotection scheme. Current reversal and weak-end infeed
functionality are available as well.

Function block

EF4PTOC (51N_67N)
I3P* TRIP
V3P* TRST1
I3PPOL* TRST2
I3PDIR* TRST3
BLOCK TRST4
BLK1 BFI_3P
BLK2 PU_ST1
BLK3 PU_ST2
BLK4 PU_ST3
PU_ST4
PUFW
PUREV
2NDHARMD
ANSI08000004-2-en.vsd
ANSI08000004 V2 EN
Figure 98: EF4PTOC (51N/67N) function block
Signals
Table 103: EF4PTOC Input signals
Name Type
I3P GROUP
SIGNAL
U3P GROUP
SIGNAL
I3PPOL GROUP
SIGNAL
Table continues on next page
Default Description
- Three phase group signal for current inputs
- Three phase group signal for polarizing voltage inputs
- Three phase group signal for polarizing current inputs
1MRK 506 335-UUS A
Technical manual