GE F650 Instruction Manual page 203

5.4 PROTECTION ELEMENTS
The Neutral Current menu incorporates the following overcurrent elements:
• Neutral time overcurrent (51N)
• Neutral instantaneous overcurrent (50N)
• Neutral directional element (67N)
5.4.4.1 NEUTRAL TIME DELAYED OVERCURRENT ELEMENT (51N)
Neutral TOC is a neutral time delayed overcurrent protection element. This element uses as the input quantity the neutral
current, calculated from the phase currents. The trip can be timed by a curve selectable by setting. The reset can be
instantaneous or linear.
Table 5–46: NEUTRAL TOC ELEMENT SETTINGS
SETPOINT > PROTECTION ELEMENTS > NEUTRAL CURRENT > NEUTRAL TOC
NEUTRAL TOC 1> NEUTRAL TOC 2 > NEUTRAL TOC 3
SETTING DESCRIPTION
Function permission
Pickup level
Curve shape
Time Dial
Reset type
Snapshot Event generation
5
The snapshot event setting enables or disables the snapshot event generation for this element.
5.4.4.2 NEUTRAL INSTANTANEOUS OVERCURRENT ELEMENT (50N)
This function can be used as an instantaneous element or as a definite time element. The element responds to the neutral
current, calculated from phase currents.
Table 5–47: NEUTRAL IOC ELEMENT SETTINGS
SETPOINT > PROTECTION ELEMENTS > NEUTRAL CURRENT > NEUTRAL IOC
NEUTRAL IOC 1> NEUTRAL IOC 2 > NEUTRAL IOC 3
SETTING DESCRIPTION
Function permission
Pickup level
Trip time
Reset time
Snapshot event generation
The snapshot event setting enables or disables the snapshot event generation for this element.
5-56
NAME DEFAULT VALUE
Function DISABLED
Pickup Level 1.00
Curve IEEE Ext Inv
TD Multiplier 1.00
Reset INSTANTANEOUS
Snapshot Events ENABLED
NAME DEFAULT
VALUE
Function DISABLED
Pickup Level 30.00
Trip Delay 0.00
Reset Delay 0.00
Snapshot Events ENABLED
F650 Digital Bay Controller
5.4.4 NEUTRAL CURRENT
STEP RANGE
N/A [DISABLED – ENABLED]
0.01 A [0.05 : 160.00]
N/A [See list of curves]
0.01 s [0.00 : 900.00]
N/A [INSTANTANEOUS – LINEAR]
N/A [DISABLED – ENABLED]
STEP RANGE
N/A [DISABLED – ENABLED]
0.01 A [0.05 : 160.00]
0.01 s [0.00 : 900.00]
0.01 s [0.00 : 900.00]
N/A [DISABLED – ENABLED]
5 SETTINGS
GEK-106310AB