GE UR Series L90, Instruction Manual, Page: 335 / 846

GE Multilin L90 Line Current Differential System 5-197
5 SETTINGS 5.6 GROUPED ELEMENTS
5
e) PHASE DIRECTIONAL OVERCURRENT (ANSI 67P, IEC PDOC/PTOC)
PATH: SETTINGS

GROUPED ELEMENTS

SETTING GROUP 1(6)

PHASE CURRENT

PHASE DIRECTIONAL 1(2)
The phase directional elements (one for each of phases A, B, and C) determine the phase current flow direction for steady
state and fault conditions and can be used to control the operation of the phase overcurrent elements via the
BLOCK
inputs
of these elements.
Figure 5–97: PHASE A DIRECTIONAL POLARIZATION
This element is intended to apply a block signal to an overcurrent element to prevent an operation when current is flowing
in a particular direction. The direction of current flow is determined by measuring the phase angle between the current from
the phase CTs and the line-line voltage from the VTs, based on the 90° or quadrature connection. If there is a requirement
to supervise overcurrent elements for flows in opposite directions, such as can happen through a bus-tie breaker, two
phase directional elements should be programmed with opposite element characteristic angle (ECA) settings.

PHASE

DIRECTIONAL 1
PHASE DIR 1
FUNCTION: Disabled
Range: Disabled, Enabled
MESSAGE
PHASE DIR 1 SIGNAL
SOURCE: SRC 1
Range: SRC 1, SRC 2, SRC 3, SRC 4
MESSAGE
PHASE DIR 1 BLOCK:
Off
Range: FlexLogic operand
MESSAGE
PHASE DIR 1
ECA: 30
Range: 0 to 359° in steps of 1
MESSAGE
PHASE DIR POL V1
THRESHOLD: 0.700 pu
Range: 0.000 to 3.000 pu in steps of 0.001
MESSAGE
PHASE DIR 1 BLOCK
WHEN V MEM EXP: No
Range: No, Yes
MESSAGE
PHASE DIR 1
TARGET: Self-reset
Range: Self-reset, Latched, Disabled
MESSAGE
PHASE DIR 1
EVENTS: Disabled
Range: Disabled, Enabled
827800A2.CDR
V BG
V CG
V AG(Faulted)
IA
ECA
set at 30°
ECA = Element Characteristic Angle at 30°
IA = operating current
Phasors for Phase A Polarization:
V Pol = V BC (1/_ECA) = polarizing voltage
×
Fault angle
set at 60° Lag
V AG (Unfaulted)
OUTPUT
S
0
1
V BC
V BC
V Pol
+90°
–90°