GE TRANSFORMER MANAGEMENT RELAY 745 Instruction Manual page 125

5 SETPOINTS
c) VOLTS-PER-HERTZ
PATH: SETPOINTS S4 ELEMENTS
VOLTS-PER-HERTZ 1
[ENTER] for more
The V/Hz element uses the ratio of the actual measured voltage at the voltage terminal and the measured system fre-
quency. For example, a measured phases-to-phase voltage of 120 volts at 60 Hz, results in a ratio of 2 V/Hz. For 115%
overload, the setting of the V/Hz minimum pickup would be 2.3 V/Hz.
The element has a linear reset characteristic. The reset time can be programmed to match the cooling characteristic of the
protected equipment. The element will fully reset after the
as an instantaneous element with no intentional delay, as a definite time element, or as an inverse timed element.
• MINIMUM OPERATING VOLTAGE: Enter the minimum value of voltage (in terms of nominal VT secondary voltage)
required to allow the Volts-per-Hertz 1 element to operate.
• VOLTS-PER-HERTZ 1 PICKUP: Enter the volts-per-hertz value (in V/Hz) above which the Volts-per-Hertz 1 element
will pickup and start the delay timer.
• VOLTS-PER-HERTZ 1 SHAPE: Select the curve shape to be used for the Volts-per-Hertz 1 element. The inverse
volts-per-hertz curve shapes are shown below.
• VOLTS-PER-HERTZ 1 DELAY: Enter the time that the volts-per-hertz value must remain above the pickup level before
the element operates.
• VOLTS-PER-HERTZ 1 RESET: Enter the time that the volts-per-hertz value must remain below the pickup level before
the element resets.
GE Multilin
Courtesy of NationalSwitchgear.com
OVEREXCITATION VOLTS-PER-HERTZ 1(2)
ð
VOLTS-PER-HERTZ 1
ENTER
FUNCTION: Disabled
ESCAPE
VOLTS-PER-HERTZ 1
ESCAPE
TARGET: Self-Reset
MESSAGE
MINIMUM OPERATING
ESCAPE
VOLTAGE: 0.10 x VT
MESSAGE
VOLTS-PER-HERTZ 1
ESCAPE
PICKUP: 2.36 V/Hz
MESSAGE
VOLTS-PER-HERTZ 1
ESCAPE
SHAPE: Definite Time
MESSAGE
VOLTS-PER-HERTZ 1
ESCAPE
DELAY: 2.00 s
MESSAGE
VOLTS-PER-HERTZ 1
ESCAPE
RESET: 0.0 s
MESSAGE
VOLTS-PER-HERTZ 1
ESCAPE
BLOCK: Disabled
MESSAGE
VOLTS-PER-HERTZ RESET
745 Transformer Management Relay
5.6 S4 ELEMENTS
Range: Enabled, Disabled
Range: Self-Reset, Latched, None
Range: 0.10 to 0.99 x VT in steps of 0.01
Range: 1.00 to 4.00 V/Hz in steps of 0.01
Range: Definite Time, Inv Curve 1, Inv Curve 2,
Inv Curve 3
Range: 0.00 to 600.00 s in steps of 0.01
Range: 0.0 to 6000.0 s in steps of 0.1
Range: Logc Inpt 1 to 16, Virt Inpt 1 to 16, Output Rly 2 to
8, SelfTest Rly, Vir Outpt 1 to 5, Disabled
value. The V/Hz function can be used
5
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