Grouped Protection Elements; Line Pickup - GE D90 Plus Instruction Manual

CHAPTER 7: PROTECTION
Use of sources example

Grouped protection elements

Line pickup

PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 161: Disturbance detector logic
Plus
Consider a D90 connected as shown. This configuration can be used on a transmission
line connected into a breaker-and-a-half system. The figure shows the arrangement of
sources used to provide the functions required in this application, and the AC module
inputs used to provide the data.
Each protection element can be assigned up to six sets of settings with designations 1 to 6.
The performance of these elements is defined by the active setting group at a given time.
Multiple setting groups allow the user to conveniently change protection settings for
different operating situations (for example, altered power system configuration or season
of the year). The active setting group can be preset or selected in the Settings > Protection
> Control > Setting Groups menu.
The line pickup feature uses a combination of undercurrent and undervoltage to identify a
line that has been de-energized (line end open). Alternately assign a FlexLogic operand to
the Terminal Open setting that specifies the terminal status. Three instantaneous
Figure 162: Use of sources example
GROUPED PROTECTION ELEMENTS
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