Schweitzer Engineering Laboratories SEL-351S - 50 GFP - Forward Directional Residual Ground Current Pickup; 50 GRP - Reverse Directional Residual Ground Current Pickup; 50 GFP and 50 GRP Set Automatically; a0 - Positive-Sequence Current Restraint Factor, I0;I1

4-32 Loss-of-Potential, Load Encroachment, and Directional Element Logic Date Code 20010112
SEL-351S Instruction Manual
50GFP – Forward Directional Residual Ground Current Pickup
50GRP – Reverse Directional Residual Ground Current Pickup
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50GFP and 50GRP Set Automatically
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a0 – Positive-Sequence Current Restraint Factor, I
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