• The directional element will be internally enabled to operate as soon as Iop is
bigger than 40% of IN>Dir and the directional condition is fulfilled in the set
direction.
• The relay characteristic angle AngleRCA, which defines the position of
forward and reverse areas in the operating characteristic.
The directional comparison will set the output binary signals:
1. STFW=1 when operating quantity magnitude Iop x cos(φ - AngleRCA) is
bigger than setting parameter IN>Dir and directional supervision element
detects fault in forward direction.
2. STRV=1 when operating quantity magnitude Iop x cos(φ - AngleRCA) is
bigger than 60% of setting parameter IN>Dir and directional supervision
element detects fault in reverse direction.
These signals shall be used for communication based earth-fault teleprotection
communication schemes (permissive or blocking).
Simplified logic diagram for directional supervision element with integrated
directional comparison step is shown in Figure
45:
Section 6 1MRK 505 384-UEN A
Current protection
120 Breaker protection REQ650 2.2 IEC
Technical manual
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