Digital Overcurrent & Ground Overvoltage & Selective Ground Relay (GDR-AEF01) User's Manual
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Kyongbo Electronics Co., Ltd.
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Figure 3.12
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INST. OVGR(IOVGR) Logic Diagram
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Figure 3.13
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TIME OVGR(TOVGR) Logic Diagram
3.2 Ground OverVoltage Function
This relay contains the Instantaneous Time characteristic, Inverse Time
characteristic, and Definite Time characteristic to be used for ground overvoltage
protection.
The inverse time characteristic is the function between voltage and time, and the
bigger the voltage, the shorter the operation time.
The time and voltage relationship function is as follows.
×
sec
T = Operation Time
V = Relay input voltage / relay operation setting value
M = Operation time ratio
Logic Diagram for ground overvoltage element operation is as follows.
