GE D90 Plus Instruction Manual page 194

GROUPED PROTECTION ELEMENTS
186
Figure 147: Load encroachment configuration settings
The following settings are available.
Function
Range: Enabled, Disabled
Default: Disabled
This setting enables and disabled the load encroachment element.
Source
Range: LINE (SRC 1), BKR 1 (SRC 2), BKR 2 (SRC 3)
Default: LINE (SRC 1)
This setting selects the signal source for the load encroachment element.
Minimum Voltage
Range: 0.000 to 3.000 pu in steps of 0.001
Default: 0.250 pu
This setting specifies the minimum positive-sequence voltage required for operation of
the element. If the voltage is below this threshold a blocking signal will not be asserted
by the element. When selecting this setting one must remember that the
Plus
D90 measures the phase-to-ground sequence voltages regardless of the VT
connection.
The nominal VT secondary voltage as specified in the
per-unit base for this setting.
Reach
Range: 0.02 to 250.00 ohms in steps of 0.01
Default: 1.00 ohms
This setting specifies the resistive reach of the element as shown in the load
encroachment characteristic. This setting should be entered in secondary ohms and be
calculated as the positive-sequence resistance seen by the relay under maximum load
conditions and unity power factor.
Angle
Range: 5 to 50° in steps of 1
Default: 30°
This setting specifies the size of the blocking region as shown on the load encroachment
characteristic diagram and applies to the positive-sequence impedance.
Pickup Delay
Range: 0.000 to 65.535 seconds in steps of 0.001
Default: 0.000 seconds
This setting specifies a delay for the declaration of the load encroachment element
between the pickup and operate output states. It is normally set to zero.
PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 7: PROTECTION
setting is the
Phase VT Secondary