ABB Relion 670 Series Technical Reference Manual page 159

1MRK 505 208-UEN B
Technical reference manual
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IEC05000745 V1 EN
Figure 73: 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 start current signal can be set:
IminOpPhSel.
If no blockings are given the start 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
characteristics".
All four steps in OC4PTOC can be blocked from the binary input BLOCK. The
binary input BLKSTx (x=1, 2, 3 or 4) blocks the operation of respective step.
Different types of reset time can be selected as described in section
characteristics".
There is also a possibility to activate a preset change (IxMult x= 1, 2, 3 or 4) of the
set operation current via a binary input (enable multiplier). In some applications the
operation value needs to be changed, for example due to changed network
switching state. The function can be blocked from the binary input BLOCK. The
start signals from the function can be blocked from the binary input BLKST. The
trip signals from the function can be blocked from the binary input BLKTR.
RCA
ROA
ROA
Forward
I
dir
Section 6
Current protection
U
ref
en05000745.vsd
"Inverse
"Inverse
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