GE D90 Plus Instruction Manual page 227

CHAPTER 7: PROTECTION
PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
Middle Limit Angle
Range: 40 to 140° in steps of 1
Default: 90°
This setting specifies the middle power swing detect characteristic. It is relevant only for
the three-step mode. A typical is close to the average of the outer and inner limit angles.
This setting applies to mho shapes only.
Inner Limit Angle
Range: 40 to 140° in steps of 1
Default: 60°
This setting specifies the inner power swing detect characteristic. The inner
characteristic is used by the out-of-step tripping function: beyond the inner
characteristic out-of-step trip action is definite (the actual trip can be delayed as per the
setting). Therefore, this angle must be selected in consideration to the power
Trip Mode
swing angle beyond which the system becomes unstable and cannot recover.
Outer Right Blinder
Range: 0.10 to 500.00 ohms in steps of 0.01
Default: 10.00 ohms
This setting specifies the resistive reach of the right blinder. The blinder applies to both
the outer "Mho" and "Quad" characteristics. Set this value suitably high if no blinder is
required for the "Mho" characteristic.
Outer Left Blinder
Range: 0.10 to 500.00 ohms in steps of 0.01
Default: 10.00 ohms
This setting specifies the resistive reach of the left blinder. The blinder applies to both the
outer "Mho" and "Quad" characteristics. Set this value high if no blinder is required for
the "Mho" characteristic.
Middle Right Blinder
Range: 0.10 to 500.00 ohms in steps of 0.01
Default: 10.00 ohms
This setting specifies the resistive reach of the right blinder. The blinder applies to both
the middle "Mho" and "Quad" characteristics. Set this value high if no blinder is required
for the "Mho" characteristic.
Middle Left Blinder
Range: 0.10 to 500.00 ohms in steps of 0.01
Default: 10.00 ohms
This setting specifies the resistive reach of the left blinder. The blinder applies to both the
middle "Mho" and "Quad" characteristics. Set this value high if no blinder is required for
the "Mho" characteristic.
Inner Right Blinder
Range: 0.10 to 500.00 ohms in steps of 0.01
Default: 10.00 ohms
This setting specifies the resistive reach of the right blinder. The blinder applies to both
the inner "Mho" and "Quad" characteristics. Set this value high if no blinder is required for
the "Mho" characteristic.
Inner Left Blinder
Range: 0.10 to 500.00 ohms in steps of 0.01
Default: 10.00 ohms
This setting specifies the resistive reach of the left blinder. The blinder applies to both the
inner "Mho" and "Quad" characteristics. Set this value high if no blinder is required for the
"Mho" characteristic.
GROUPED PROTECTION ELEMENTS
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