ABB Relion 670 series, Technical Reference Manual, Page: 392 / 1232

V
ref
I
dir
RCA
ROA
Forward
Reverse
ROA
en05000745_ansi.vsd
ANSI05000745 V1 EN
Figure 202: Directional characteristic of the phase overcurrent protection
The default value of AngleRCA is –65°. The parameters AngleROA gives the angle
sector from AngleRCA for directional borders.
A minimum current for directional phase pickup current signal can be set:
PUMinOpPhSel .
If no blockings are given the pickup signals will start the timers of the step. The time
characteristic for each step can be chosen as definite time delay or inverse time
characteristic. A wide range of standardized inverse time characteristics is available. It
is also possible to create a tailor made time characteristic. The possibilities for inverse
time characteristics are described in section
"Inverse characteristics" .
All four steps in OC4PTOC (51/67) can be blocked from the binary input BLOCK.
The binary input BLKx (x=1, 2, 3 or 4) blocks the operation of respective step.
Section 7
1MRK505222-UUS C
Current protection
386
Technical reference manual