ABB Relion 670 series, Technical Reference Manual

Page: 227 / 1232

The setting of the load encroachment function may influence the total operating
characteristic, (for more information, refer to section
"Load encroachment" ).
The input DIRCND contains binary coded information about the directional coming
from the directional function . It shall be connected to the STDIR output on ZDRDIR,
directional measuring block. This information is also transferred to the input DIRCND
on the distance measuring zones, that is, the ZMQPDIS, distance measuring block.
The code built up for the directionality is as follows:
STDIR= FWD_A*1+FWD_B*2+FWD_C*4+FWD_AB*8+
+FWD_BC*16+FWD_CA*32+REV_A*64+REV_B*128+REV_C*256+
+REV_AB*512+REV_BC*1024+REV_CA*2048
If the binary information is 1 then it will be considered that we have pickup in forward
direction in phase A. If the binary code is 3 then we have pickup in forward direction
in phase A and B, binary code 192 means pickup in reverse direction in phase L1 and
L2A and B etc.
The PHSELZ or DLECND output contains, in a similar way as DIRCND, binary coded
information, in this case information about the condition for opening correct fault loop
in the distance measuring element. It shall be connected to the PHSEL input on the
ZMQPDIS, distance measuring block.
The code built up for release of the measuring fault loops is as follows:
PHSEL = AG*1+BG*2+CG*4+AB*8+BC*16+CA*32
6.3.3.1 Phase-to-ground fault
Index PHS in images and equations reference settings for Phase
selection with load encroachment function FDPSPDIS (21).
( , )
( , )
PHS
n
VA B C
IA B C
Z =
EQUATION1554 V1 EN
(Equation 24)
where:
n
corresponds to the particular phase (n=1, 2 or 3)
1MRK505222-UUS C
Section 6
Impedance protection
221
Technical reference manual