GE D90 Plus Instruction Manual page 341

CHAPTER 7: PROTECTION
Recloser curve editing
PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 268: FlexCurve™ display example
Prospective FlexCurves™ can be configured from a selection of standard curves to provide
the best approximate fit, then specific data points can be edited afterwards. Click the
Initialize FlexCurve button to populate the pickup values with the points from the curve
specified by the
Initialize From
curve. Note that the pickup multiples start at zero (implying the reset time), operating time
below pickup, and operating time above pickup. Click on the Clear FlexCurve button to
reset all pickup values to zero.
Curve data can be imported from CSV (comma-separated values) files by clicking on the
Import Data From button. Likewise, curve data can be saved in CSV format by clicking the
Export Data To button. CSV is a delimited data format with fields separated by the comma
character and records separated by new lines. Refer to IETF RFC 4180 for additional
details.
Recloser curve selection is special in that recloser curves can be shaped into a composite
curve with a minimum response time and a fixed time above a specified pickup multiples.
There are 41 recloser curve types supported. These definite operating times are useful to
coordinate operating times, typically at higher currents and where upstream and
downstream protective devices have different operating characteristics. The recloser
curve configuration window shown below appears when the
"Recloser Curve" and the Initialize FlexCurve button is clicked.
setting. These values can then be edited to create a custom
CONTROL ELEMENTS
Initialize From setting is set to
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