Schweitzer Engineering Laboratories SEL-351S - 50 QFP - Forward Directional Negative-Sequence Current Pickup; 50 QRP - Reverse Directional Negative-Sequence Current Pickup; 50 QFP and 50 QRP Set Automatically; a2 - Positive-Sequence Current Restraint Factor, I2;I1

4-30 Loss-of-Potential, Load Encroachment, and Directional Element Logic Date Code 20010112
SEL-351S Instruction Manual
50QFP – Forward Directional Negative-Sequence Current Pickup
50QRP – Reverse Directional Negative-Sequence Current Pickup
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a2 – Positive-Sequence Current Restraint Factor, I
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