Operation Principle - ABB RES670 Technical Manual

1MRK 511 408-UUS A
8.1.7
Phasor measurement unit RES670 2.2 ANSI
Technical manual
Name Type
IA REAL
IB REAL
IC REAL

Operation principle

Directional phase overcurrent protection, four steps OC4PTOC (51_67) is divided into
four different sub-functions. For each step x , where x is step 1, 2, 3 and 4, an operation
mode is set by DirModeSelx: Disable/Non-directional/Forward/Reverse.
The protection design can be divided into four parts:
• The direction element
• The harmonic restraint blocking function
• The four step overcurrent function
• The mode selection
If VT inputs are not available or not connected, setting parameter
DirModeSelx shall be left to default value, Non-directional.
Values (Range) Unit
- A
- A
- A
Section 8
Current protection
Description
Current in phase A
Current in phase B
Current in phase C
M12883-3 v10
179