GE B30 Instruction Manual page 433

CHAPTER 5: SETTINGS
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
setting is "Definite Time." The source assigned to this element must be configured for a phase VT.
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.
5.7.8.5 Auxiliary overvoltage (ANSI 59X, IEC PTOV)
SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  VOLTAGE ELEMENTS  AUXILIARY OV1(3)
 AUXILIARY OV1

The B30 contains one auxiliary overvoltage element for each VT bank. This element is intended for monitoring overvoltage
conditions of the auxiliary voltage. The nominal secondary voltage of the auxiliary voltage channel entered under
SETUP  AC INPUTS  VOLTAGE BANK X5  AUXILIARY VT X5 SECONDARY
pickup level.
B30 BUS DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
SETTINGS  SYSTEM SETUP  AC INPUTS  VOLTAGE BANK  PHASE
Figure 5-118: Neutral overvoltage1 logic
AUX OV1

FUNCTION: Disabled
AUX OV1 SIGNAL

SOURCE: SRC 1
AUX OV1 PICKUP:

0.300 pu
AUX OV1 PICKUP

DELAY: 1.00 s
AUX OV1 RESET

DELAY: 1.00 s
AUX OV1 BLOCK:

Off
AUX OV1 TARGET:

Self-reset
AUX OV1 EVENTS:

Disabled
setting applies only if the
NEUTRAL OV1 PICKUP DELAY
Range: Disabled, Enabled
Range: SRC 1, SRC 2, SRC 3, SRC 4, SRC 5, SRC 6
Range: 0.004 to 3.000 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
is the per-unit (pu) base used when setting the
GROUPED ELEMENTS
5
SYSTEM
5-225