ABB REC650 ANSI Technical Manual page 96

Section 6
Current protection
faultState
I3P
V3P
ANSI05000740 V2 EN
Figure 31: Functional overview of OC4PTOC (51/67)
90
• The direction element
• The harmonic Restraint Blocking function
• The four step over current function
• The mode selection
If VT inputs are not available or not connected, setting parameter
DirModeSelx shall be left to default value, Non-directional.
dirPhAFlt
Direction
Element
dirPhBFlt
dirPhCFlt
Harmonic
harmRestrBlock
Restraint
Element
enableDir
Mode Selection
enableStep1-4
DirectionalMode1-4
The sampled analog phase currents are processed in a pre-processing function block.
Using a parameter setting MeasType within the general settings for the four step phase
overcurrent protection 3-phase output function OC4PTOC (51/67), it is possible to select
1MRK 511 287-UUS A
4 step over current
element
One element for each
step
ANSI05000740-2-en.vsd
Technical manual
faultState
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