ABB RELION RET670, Applications Manual

Page: 399 / 1016

Both current limits IMinOpPGZx and IMinOpPPZx are automatically reduced to 75%
of regular set values if the zone is set to operate in reverse direction, that is,
OperationDir is set to Reverse .
OpModePPZx and OpModePEZx
These settings, two per zone (x=1,2..5&RV), with options {Off, Quadrilateral, Mho,
Offset}, are used to set the operation and characteristic for phase-to-earth and phase-to-
phase faults, respectively.
For example, in one zone it is possible to choose Mho characteristic for the three Ph-Ph
measuring loops and Quadrilateral characteristic for the three Ph-E measuring loops.
DirModeZx
This setting defines the operating direction for zones Z3, Z4 and Z5 (the directionality
of zones Z1, Z2 and ZRV is fixed). The options are
Non-directional , Forward or
Reverse . The result from respective set value is illustrated in figure 186 , where the
positive impedance corresponds to the direction out on the protected line.
IEC05000182-2-en.vsdx
R
X
R
X
R
X
Non-directional Forward Reverse
IEC05000182 V2 EN-US
Figure 186: Directional operating modes of the distance measuring zones 3 to 5
tPPZx , tPGZx , TimerModeZx , ZoneLinkPU and TimerLinksZx
The logic for the linking of the timer settings can be described with a module diagram.
The following figure shows only the case when
TimerModeZx is selected to Ph-Ph and
Ph-G .
1MRK 504 163-UUS A
Section 8
Impedance protection
Transformer protection RET670 2.2 ANSI 393
Application manual