SERVICE MANUAL R5888C
QUADRAMHO Chapter 2
Page 67 of 74
Zone 1 positive sequence Z1 = (K11 + K12 + K13) K14 x Z
Ph
Ω
Extended Zone 1 Z1X = Z1 x K15 Ω
Zone 2 Z2 = (K21 + K22) K24 x Z
Ph
Ω
Zone 3 Z3 = (K31 + K32) K33 x Z
Ph
Ω
Zone 3 reverse Z3' = (K35 + K36) K33 x K37 x Z
Ph
Ω
6.3 Resistive reach setting range (quadrilateral earth fault units only)
The resistive reach in both the forward and reverse direction for Zones 1, 2 and 3
are set by switch K3.
Resistive reach RS =
K3
Ω
I
n
6.4 Lenticular aspect ratio setting range (lenticular zone 3 only)
The aspect ratio a/b of the lenticular Zone 3 phase fault and earth fault units and
of the Zone 6 power swing blocking zone is 0.41, 0.67 or 1.00, where b is the
sum of the forward and reverse reach settings and a is the maximum width of the
impedance characteristic measured perpendicular to the characteristic angle.
Aspect ratio 1.00 gives a circular characteristic.
6.5 Summary of K-factors
K1 0 to 4 step 1
K2 0 to 0.8 step 0.2
K3 8, 16, 32, 40, 38 *if fitted)
K4 0 to 5 step 1
K5 0 to 0.9 step 0.1
K6 0. to 0.8 step 0.02
K11 1 to 9 step 1 (and infinity)
K12 0 to 0.9 step 0.1
K13 0 to 0.08 step 0.02
K14 1, 5
K15 1 to 2 step 0.1 and infinity
K21 1 to 9 step 1 (and infinity)
K22 0 to 0.9 step 0.1
K31 1 to 9 step 1
K 32 0 to 0.9 step 0.1
K33 1, 5
a/b 0.41, 0.67, 1.00 (if fitted)
K35 1 to 9 step 1
K36 0 to 0.9 step 0.1
K37 0.25, 0.5, 1.0
The infinity positions of K11, K15 and K21 are used for on-load directional
checks. With the exception of K37 any unused switch positions are at the most
clockwise positions of the switch knob and have the same electrical connection as
the highest setting used.
To Next Page
Loading...