GE D60 Instruction Manual page 267

5 SETTINGS
• PHS DIST Z1 XFMR VOL CONNECTION: The phase distance elements can be applied to look through a three-phase
delta-wye or wye-delta power transformer. In addition, VTs and CTs could be located independently from one another
at different windings of the transformer. If the potential source is located at the correct side of the transformer, this set-
ting shall be set to "None".
This setting specifies the location of the voltage source with respect to the involved power transformer in the direction
of the zone. The following figure illustrates the usage of this setting. In section (a), zone 1 is looking through a trans-
former from the delta into the wye winding. Therefore, the Z1 setting shall be set to "Dy11". In section (b), Zone 4 is
looking through a transformer from the wye into the delta winding. Therefore, the Z4 setting shall be set to "Yd1". The
zone is restricted by the potential point (location of the VTs) as illustrated in Figure (e).
• PHS DIST Z1 XFMR CUR CONNECTION: This setting specifies the location of the current source with respect to the
involved power transformer in the direction of the zone. In section (a) of the following figure, zone 1 is looking through
a transformer from the delta into the wye winding. Therefore, the Z1 setting shall be set to "Dy11". In section (b), the
CTs are located at the same side as the read point. Therefore, the Z4 setting shall be set to "None".
See the Theory of operation chapter for more details, and the Application of settings chapter for information on calcu-
lating distance reach settings in applications involving power transformers.
(a)
Z4
Z4 XFRM VOL CONNECTION = None
Z4 XFRM CUR CONNECTION = None
Z1 XFRM VOL CONNECTION = Dy11
Z1 XFRM CUR CONNECTION = Dy11
(c)
Z4
Z4 XFRM VOL CONNECTION = None
Z4 XFRM CUR CONNECTION = Yd1
Z1 XFRM VOL CONNECTION = Dy11
Z1 XFRM CUR CONNECTION = None
Figure 5–63: APPLICATIONS OF THE
• PHS DIST Z1 REACH: This setting defines the zone reach for the forward and reverse applications. In the non-direc-
tional applications, this setting defines the forward reach of the zone. The reverse reach impedance in non-directional
applications is set independently. The reach impedance is entered in secondary ohms. The reach impedance angle is
entered as the
PHS DIST Z1 RCA
Zone 1 is characterized by transient overreach of less than 5% under source impedance ratios of up to 30. When set-
ting an under-reaching zone 1 for direct tripping and under-reaching pilot schemes (DUTT, PUTT) other factors should
be also considered as per rules of distance relaying. In non-directional applications, this 5% transient accuracy applies
to the forward reach only.
• PHS DIST Z1 RCA: This setting specifies the characteristic angle (similar to the 'maximum torque angle' in previous
technologies) of the phase distance characteristic for the forward and reverse applications. In the non-directional appli-
cations, this setting defines the angle of the forward reach impedance. The reverse reach impedance in the non-direc-
GE Multilin
delta wye, 330 o lag
Z1
delta wye, 330 o lag
Z1
PH DIST XFMR VOL/CUR CONNECTION
setting.
D60 Line Distance Protection System
5.6 GROUPED ELEMENTS
(b)
delta wye, 330 o
Z4
Z4 XFRM VOL CONNECTION = Yd1
Z4 XFRM CUR CONNECTION = None
Z1
Z1 XFRM VOL CONNECTION = None
Z1 XFRM CUR CONNECTION = Dy11
(e)
L
1
Zone 4
Zone 1
Z Z Z
L1 T L2
SETTINGS
lag
L
2
5-133
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