Schweitzer Engineering SEL-351P, Quick Start Manual

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Date Code 990430 Loss-of-Potential, Load Encroachment, and Directional Element Logic 4-27
SEL-351P Manual Técnico
D
IRECTIONAL
C
ONTROL
S
ETTINGS
The directional control for overcurrent elements is enabled by making directional control enable
setting E32. Setting E32 has setting choices:
Y enable directional control
N disable directional control
AUTO enable directional control and set a number of the directional element settings
automatically
Note : If directional control enable setting E32 = N, directional control is disabled and no
directional control settings are made. All level direction settings are set internally as:
DIR1 = N (no directional control for Level 1 overcurrent elements)
DIR2 = N (no directional control for Level 2 overcurrent elements)
DIR3 = N (no directional control for Level 3 overcurrent elements)
DIR4 = N (no directional control for Level 4 overcurrent elements)
With the above settings, the directional control outputs in Figure SECTION 4: .14,
Figure SECTION 4: .15, Figure SECTION 4: .20, and Figure SECTION 4: .21 assert
to logical 1. The referenced overcurrent elements in Figure SECTION 4: .14,
Figure SECTION 4: .15, Figure SECTION 4: .20, and Figure SECTION 4: .21 are
then not controlled by the directional control logic.
Settings Made Automatically
If the directional control enable setting E32 is set:
E32 = AUTO
then the following directional control settings are calculated and set automatically:
Z2F, Z2R, 50QFP, 50QRP, a2, k2, 50GFP, 50GRP, a0, Z0F, and Z0R
Once these settings are calculated automatically, they can only be modified if the user goes back
and changes the directional control enable setting to E32 = Y.
The remaining directional control settings are not set automatically if setting E32 = AUTO.
They have to be set by the user, whether setting E32 = AUTO or Y. These settings are:
DIR1, DIR2, DIR3, DIR4, ORDER, 50P32P, and E32IV
All these settings are explained in detail in the remainder of this subsection.