GE Multilin F650

GE Multilin F650 Digital Bay Controller 5-49
5 SETPOINTS 5.4 PROTECTION ELEMENTS
5
5.4.4 NEUTRAL CURRENT
The F650 Neutral Current menu incorporates the following overcurrent elements:
• Neutral time overcurrent (51N)
• Neutral instantaneous overcurrent (50N)
• Neutral directional unit (67N)
5.4.4.1 NEUTRAL TIME DELAYED OVERCURRENT UNIT (51N)
Unit 51N is a neutral time delayed overcurrent protection element. This unit uses as input quantity the neutral current,
calculated from the phase currents. Trip can be timed by a curve selectable by setpoint. Reset can be instantaneous or
linear.
Table 5–44: 51N UNIT SETPOINTS
The snapshot event setpoint enables or disables the snapshot event generation for this unit.
5.4.4.2 NEUTRAL INSTANTANEOUS OVERCURRENT UNIT (50N)
This function can be used as an instantaneous unit or as a definite time unit. The unit responds to the neutral current
fundamental harmonic magnitude, calculated from the phase currents.
Table 5–45: 50N UNIT SETPOINTS
The snapshot event setpoint enables or disables the snapshot event generation for this unit.
SETPOINT > PROTECTION ELEMENTS > NEUTRAL CURRENT > NEUTRAL TOC
NEUTRAL TOC 1> NEUTRAL TOC 2 > NEUTRAL TOC 3
SETPOINT DESCRIPTION NAME DEFAULT VALUE STEP RANGE
Function permission Function DISABLED N/A [DISABLED – ENABLED]
Pickup level Pickup Level 1.00 0.01 A [0.05 : 160.00]
Curve shape Curve IEEE Ext Inv N/A [See list of curves]
Time Dial TD Multiplier 1.00 0.01 s [0.00 : 900.00]
Reset type Reset INSTANTANEOUS N/A [INSTANTANEOUS – LINEAR]
Snapshot Event generation Snapshot Events ENABLED N/A [DISABLED – ENABLED]
SETPOINT > PROTECTION ELEMENTS > NEUTRAL CURRENT > NEUTRAL IOC
NEUTRAL IOC 1> NEUTRAL IOC 2 > NEUTRAL IOC 3
SETPOINT DESCRIPTION NAME DEFAULT
VALUE
STEP RANGE
Function permission Function DISABLED N/A [DISABLED – ENABLED]
Pickup level Pickup Level 30.00 0.01 A [0.05 : 160.00]
Trip time Trip Delay 0.00 0.01 s [0.00 : 900.00]
Reset time Reset Delay 0.00 0.01 s [0.00 : 900.00]
Snapshot event generation Snapshot Events ENABLED N/A [DISABLED – ENABLED]