ABB Relion 670 Series Technical Reference Manual page 413

1MRK505222-UUS C
Technical reference manual
• Directional element will be internally enabled to operate as soon as Iop is bigger
than 40% of IDirPU and directional condition is fulfilled in set direction.
• Relay characteristic angle AngleRCA, which defines the position of forward and
reverse areas in the operating characteristic.
Directional comparison step, built-in within directional supervision element, will set
EF4PTOC (51N/67N) function output binary signals:
1. PUFW=1 when operating quantity magnitude Iop x cos(φ - AngleRCA) is bigger
than setting parameter IDirPU and directional supervision element detects fault in
forward direction.
2. PUREV=1 when operating quantity magnitude Iop x cos(φ - AngleRCA) is bigger
than 60% of setting parameter IDirPU and directional supervision element detects
fault in reverse direction.
These signals shall be used for communication based ground-fault teleprotection
communication schemes (permissive or blocking).
Simplified logic diagram for directional supervision element with integrated directional
comparison step is shown in figure 208:
Section 7
Current protection
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