Operation Principle - ABB REG650 Technical Manual

Section 7
Impedance protection
Table 44: ZGCPDIS (21G) Non group settings (basic)
Name Values (Range)
GlobalBaseSel 1 - 6
7.1.6
7.1.6.1
7.1.6.2
136
Unit Step
- 1

Operation principle

Full scheme measurement
The execution of the different fault loops for phase-to-phase faults are executed in
parallel. The use of full scheme technique gives faster operation time compared to the
switched schemes that uses a pickup element to select correct voltage and current
depending on the fault type.
Impedance characteristic
The distance function consists of three zones. Each zone is self polarized offset mho
characteristics with reverse offset. The operating characteristic is in accordance to
figure 59.
Default Description
1 Selection of one of the Global Base Value
groups
1MRK 502 043-UUS B
Technical Manual