GE T60, Instruction Manual

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5-188 T60 Transformer Protection System GE Multilin
5.6 GROUPED ELEMENTS 5 SETTINGS
5
Figure 5–76: APPLICATIONS OF THE
PH DIST XFMR VOL/CUR CONNECTION
SETTINGS
• 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
setting.
To achieve specified operating speed of distance elements, the relay internally calculates source to line impedance
ratio (SIR) from fault phasors. In these calculations, line impedance is estimated based on the zone 1 reach setting.
Therefore, in order to calculate the SIR value properly and to maintain the optimal operating speed of the distance ele-
ments, you need to set zone 1 reach with a regular 80 to 85% of the line impedance reach setting, even when zone 1
is disabled.
• 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-
tional applications is set independently. The setting is an angle of reach impedance as shown in the distance
characteristic figures shown earlier. This setting is independent from
PHS DIST Z1 DIR RCA
, the characteristic angle of an
extra directional supervising function.
• PHS DIST Z1 REV REACH : This setting defines the reverse reach of the zone set to non-directional (
PHS DIST Z1 DIR
setting). The value must be entered in secondary ohms. This setting does not apply when the zone direction is set to
“Forward” or “Reverse”.
• PHS DIST Z1 REV REACH RCA : This setting defines the angle of the reverse reach impedance if the zone is set to
non-directional (
PHS DIST Z1 DIR
setting). This setting does not apply when the zone direction is set to “Forward” or
“Reverse”.
• PHS DIST Z1 COMP LIMIT: This setting shapes the operating characteristic. In particular, it produces the lens-type
characteristic of the mho function and a tent-shaped characteristic of the reactance boundary of the quadrilateral func-
tion. If the mho shape is selected, the same limit angle applies to both the mho and supervising reactance compara-
tors. In conjunction with the mho shape selection, the setting improves loadability of the protected line. In conjunction
830717A1.CDR
Z1
Z3
Z 3 X F RM V OL CO NNE CT I O N = N one
Z 3 X F RM CUR CO NNE CT I O N = N one
Z 1 X F RM V OL CO NNE CT I O N = Dy11
Z 1 X F RM CUR CO NNE CT I O N = Dy11
de l ta wy e , 330
o
l ag
(a)
Z1
Z3
Z 3 X F RM V OL CO NNE CT I O N = Yd1
Z 3 X F RM CUR CO NNE CT I O N = N one
Z 1 X F RM V OL CO NNE CT I O N = N one
Z 1 X F RM CUR CO NNE CT I O N = Dy11
de l ta wy e , 330
o
l ag
( b )
Z1
Z3
Z 3 X F RM V OL CO NNE CT I O N = N one
Z 3 X F RM CUR CO NNE CT I O N = Yd1
Z 1 X F RM V OL CO NNE CT I O N = Dy11
Z 1 X F RM CUR CO NNE CT I O N = N one
de l ta wy e , 330
o
l ag
( c )
Z one 1
Z one 3
(e)
L
1
L
2
Z
L 1
Z
T
Z
L 2