ABB REB650 - Operation Principle

7.1.7 Operation principle
The protection design can be decomposed in four parts:
• 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.
en05000740_ansi.vsd
Direction
Element
4 step over current
element
One element for each
step
Harmonic
Restraint
Mode Selection
dirPhAFlt
dirPhBFlt
dirPhCFlt
harmRestrBlock
enableDir
enableStep1-4
DirectionalMode1-4
faultState
Element
faultState
I3P
V3P
I3P
PICKUP
TRIP
ANSI05000740 V1 EN
Figure 32: Functional overview of OC4PTOC (51/67)
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
Section 7 1MRK 505 277-UUS C
Current protection
78
Technical Manual