GE L60 Instructions Manual page 498

GROUPED ELEMENTS
There are three neutral overvoltage elements available. The neutral overvoltage element can be used to detect
asymmetrical system voltage condition due to a ground fault or to the loss of one or two phases of the source. The
element responds to the system neutral voltage (3V_0), calculated from the phase voltages. The nominal secondary
voltage of the phase voltage channels entered under
is the p.u. base used when setting the pickup level.
VT SECONDARY
The neutral overvoltage element can provide a time-delayed operating characteristic versus the applied voltage (initialized
from FlexCurves A, B, or C) or be used as a definite time element. The
NEUTRAL OV1 CURVE
VT errors and normal voltage unbalance must be considered when setting this element. This function requires the VTs to
be wye-connected.
5
5.6.14.5 Negative sequence overvoltage (ANSI 59Q, IEC PTOV)
SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  VOLTAGE ELEMENTS  NEG SEQ OV1(3)
 NEG SEQ OV1

There are three negative-sequence overvoltage elements available.
Use the negative-sequence overvoltage element to detect loss of one or two phases of the source, a reversed phase
sequence of voltage, or a non-symmetrical system voltage condition.
5-290
setting is "Definite Time." The source assigned to this element must be configured for a phase VT.
Figure 5-163: Neutral overvoltage1 logic
NEG SEQ OV1

FUNCTION: Disabled
NEG SEQ OV1 SIGNAL

SOURCE: SRC 1
NEG SEQ OV1 PICKUP:

0.300 pu
NEG SEQ OV1 PICKUP

DELAY: 0.50 s
NEG SEQ OV1 RESET

DELAY: 0.50 s
NEG SEQ OV1 BLOCK:

Off
NEG SEQ OV1 TARGET:

Self-reset
NEG SEQ OV1 EVENTS:

Disabled
SETTINGS  SYSTEM SETUP  AC INPUTS  VOLTAGE BANK  PHASE
NEUTRAL OV1 PICKUP DELAY
Range: Disabled, Enabled
Range: SRC 1, SRC 2, SRC 3, SRC 4
Range: 0.004 to 1.250 pu in steps of 0.001
Range: 0.00 to 600.00 s in steps of 0.01
Range: 0.00 to 600.00 s in steps of 0.01
Range: FlexLogic operand
Range: Self-reset, Latched, Disabled
Range: Disabled, Enabled
L60 LINE PHASE COMPARISON SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS
setting applies only if the