Sel 411L - Figure 3.130 Quadrilateral Phase Distance Element Characteristic (TANGP = 0)

P.3.192
SEL-411L Relay Protection Manual Date Code 20151029
Protection Functions
Quadrilateral Phase Distance Elements
Because Zone 1 and Zone 2 operate in the forward direction, the left blinder in
the reverse direction is the lowest setting among Zones m (m = 3–5). Zones set
to OFF (XPm = OFF), forward looking zones (DIRm = F) and zones not
included in the E21XP setting are excluded from the calculations to determine
the minimum RP value in the reverse direction.
TANGP, the tilt angle setting, tilts the reactance values, but does not affect the
resistance values. Figure 3.130 shows the quadrilateral phase characteristic
with TANGP = 0 degrees.
Figure 3.131 shows the quadrilateral phase distance element characteristic
with TANGP = –10 degrees. Notice that the reactance elements are tilted by
10 degrees, but the resistance blinders are unaffected by this setting. Also
notice that the pivot point of the tilt is the line impedance and not the reactance
axis. Furthermore, there are no individual TANGP settings for each zone;
when you enter a value other than zero for TANGP, all enabled zones are tilted
by the same value.
Figure 3.130 Quadrilateral Phase Distance Element Characteristic (TANGP = 0)
Zone 3
Zone 2
Zone 1
Z1ANG
RP1
XP1
XP2
XP3
jX
—RP RP2 RP3
R