5-254
F35 MULTIPLE FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
GROUPED ELEMENTS
CHAPTER 5: SETTINGS
5
VT errors and normal voltage unbalance must be considered when setting this element. This function requires the VTs to
be wye-connected.
Figure 5-137: Neutral overvoltage1 logic
5.7.8.5 Auxiliary undervoltage (ANSI 27X, IEC PTUV)
SETTINGS
GROUPED ELEMENTS
SETTING GROUP 1(6)
VOLTAGE ELEMENTS
AUXILIARY UV1(3)
The F35 contains one auxiliary undervoltage element for each VT bank. This element monitors undervoltage conditions of
the auxiliary voltage.
The
AUX UV1 PICKUP
selects the voltage level at which the time undervoltage element starts timing. The nominal secondary
voltage of the auxiliary voltage channel entered under
SETTINGS
SYSTEM SETUP
AC INPUTS
VOLTAGE BANK X5
AUXILIARY VT X5 SECONDARY
is the per-unit base used when setting the pickup level.
The
AUX UV1 DELAY
setting selects the minimum operating time of the auxiliary undervoltage element.
Both
AUX UV1 PICKUP
and
AUX UV1 DELAY
settings establish the operating curve of the undervoltage element. The auxiliary
undervoltage element can be programmed to use either definite time delay or inverse time delay characteristics. The
operating characteristics and equations for both definite and inverse time delay are as for the phase undervoltage
element.
The element resets instantaneously. The minimum voltage setting selects the operating voltage below which the element
is blocked.
AUXILIARY UV1
AUX UV1
FUNCTION: Disabled
Range: Disabled, Enabled
AUX UV1 SIGNAL
SOURCE: SRC 1
Range: SRC 1, SRC 2, SRC 3, SRC 4, SRC 5, SRC 6
AUX UV1 PICKUP:
0.700 pu
Range: 0.004 to 3.000 pu in steps of 0.001
AUX UV1 CURVE:
Definite Time
Range: Definite Time, Inverse Time
AUX UV1 DELAY:
1.00 s
Range: 0.00 to 600.00 s in steps of 0.01
AUX UV1 MINIMUM:
VOLTAGE: 0.100 pu
Range: 0.000 to 3.000 pu in steps of 0.001
AUX UV1 BLOCK:
Off
Range: FlexLogic operand
AUX UV1 TARGET:
Self-reset
Range: Self-reset, Latched, Disabled
AUX UV1 EVENTS:
Disabled
Range: Disabled, Enabled
