GE UR series Instruction Manual page 200

5.3 SYSTEM SETUP
AC input actual values:
The calculated parameters associated with the configured voltage and current inputs are displayed in the current and volt-
age sections of actual values. Only the phasor quantities associated with the actual AC physical input channels will be dis-
played here. All parameters contained within a configured source are displayed in the sources section of the actual values.
DISTURBANCE DETECTORS (INTERNAL):
The disturbance detector (ANSI 50DD) element is a sensitive current disturbance detector that detects any disturbance on
the protected system. The 50DD function is intended for use in conjunction with measuring elements, blocking of current
based elements (to prevent maloperation as a result of the wrong settings), and starting oscillography data capture. A dis-
turbance detector is provided for each source.
The 50DD function responds to the changes in magnitude of the sequence currents. The disturbance detector scheme
logic is as follows:
5
The disturbance detector responds to the change in currents of twice the current cut-off level. The default cut-off threshold
is 0.02 pu; thus by default the disturbance detector responds to a change of 0.04 pu. The metering sensitivity setting (
UCT SETUP DISPLAY PROPERTIES
accordingly.
EXAMPLE USE OF SOURCES:
An example of the use of sources is shown in the diagram below. A relay could have the following hardware configuration:
This configuration could be used on a two-winding transformer, with one winding connected into a breaker-and-a-half sys-
tem. The following figure shows the arrangement of sources used to provide the functions required in this application, and
the CT/VT inputs that are used to provide the data.
5-68
ACTUAL
SOURCE 1
CURRENT PHASOR
_1
_2
_0
ACTUAL
SOURCE 2
CURRENT PHASOR
_1
_2
_0
ACTUAL
SOURCE 6
CURRENT PHASOR
_1
_2
_0
Figure 5–17: DISTURBANCE DETECTOR LOGIC DIAGRAM
CURRENT CUT-OFF LEVEL
L60 Line Phase Comparison System
SETTING
PRODUCT SETUP/DISPLAY
PROPERTIES/CURRENT
CUT-OFF LEVEL
_1 - _1' >2*CUT-OFF FLEXLOGIC OPERAND
_2 - _2' >2*CUT-OFF OR SRC 1 50DD OP
_0 - _0' >2*CUT-OFF
Where ' is 2 cycles old
SETTING
PRODUCT SETUP/DISPLAY
PROPERTIES/CURRENT
CUT-OFF LEVEL
_1 - _1' >2*CUT-OFF FLEXLOGIC OPERAND
SRC 2 50DD OP
_2 - _2' >2*CUT-OFF OR
_0 - _0' >2*CUT-OFF
Where ' is 2 cycles old
SETTING
PRODUCT SETUP/DISPLAY
PROPERTIES/CURRENT
CUT-OFF LEVEL
_1 - _1' >2*CUT-OFF FLEXLOGIC OPERAND
_2 - _2' >2*CUT-OFF OR SRC 6 50DD OP
_0 - _0' >2*CUT-OFF
Where ' is 2 cycles old
827092A3.CDR
) controls the sensitivity of the disturbance detector
5 SETTINGS
PROD-
GE Multilin