ABB Relion 650 Series Technical Manual page 87

1MRK 506 326-UUS B
Distance protection zones
The design of the distance protection zones are presented for all measuring loops: phase-to-
ground as well as phase-to-phase.
Phase-to-ground related signals are designated by AG, BG and CG. The phase-to-phase signals are
designated by AB, BC and CA.
Fulfillment of two different measuring conditions is necessary to obtain the one logical signal for
each separate measuring loop:
• Zone measuring condition, which follows the operating equations described above.
• Group functional input signal (PHSEL), as presented in figure 37.
The PHSEL input signal represents a connection of six different integer values from Phase
selection with load encroachment, quadrilateral characteristic function FDPSPDIS (21) within the
IED, which are converted within the zone measuring function into corresponding boolean
expressions for each condition separately. Input signal PHSEL is connected to FDPSPDIS (21)
function output STCNDZI.
PHSEL
AB
BC
CA
AG
BG
CG
BLKZ
BLOCK
ANSI09000243 V1 EN-US
Figure 37: Conditioning by a group functional input signal PHSEL, external start condition
Results of the directional measurement enter the logic circuits, when the zone operates in
directional (forward or reverse) mode, as shown in figure 38.
Line distance protection REL650
Technical manual
OR
AND
AND
AND
AND
AND
AND
OR
OR
© Copyright 2011 ABB Power Grids. All rights reserved
STNDCG
OR
STND
AND
BLK
ANSI09000243-1-en.vsd
Section 5
Impedance protection
M13841-10 v6
STNDAB
STNDBC
STNDCA
STNDAG
STNDBG
81