Overfrequency 1 - GE UR Series F60 Instruction Manual

5 SETTINGS
load and generation is to automatically disconnect selected loads, based on the actual system frequency. This technique,
called "load-shedding", maintains system integrity and minimize widespread outages. After the frequency returns to normal,
the load may be automatically or manually restored.
The setting is used to select the source for the signal to be measured. The element first checks for a
UNDERFREQ 1 SOURCE
live phase voltage available from the selected source. If voltage is not available, the element attempts to use a phase cur-
rent. If neither voltage nor current is available, the element will not operate, as it will not measure a parameter below the
minimum voltage/current setting.
The
UNDERFREQ 1 MIN VOLT/AMP
quency element to operate. This threshold is used to prevent an incorrect operation because there is no signal to measure.
This setting is used to select the level at which the underfrequency element is to pickup. For example,
UNDERFREQ 1 PICKUP
if the system frequency is 60 Hz and the load shedding is required at 59.5 Hz, the setting will be 59.50 Hz.
SETTING
UNDERFREQ 1 FUNCTION:
Disabled = 0
Enabled = 1
SETTING
UNDERFREQ 1 BLOCK:
Off = 0
SETTING
ACTUAL VALUES
UNDERFREQ 1 SOURCE:
Level
VOLT / AMP
Frequency
PATH: SETTINGS CONTROL ELEMENTS

OVERFREQUENCY 1

MESSAGE
MESSAGE
MESSAGE
MESSAGE
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MESSAGE
There are four overfrequency elements, numbered 1 through 4.
A frequency calculation for a given source is made on the input of a voltage or current channel, depending on which is
available. The channels are searched for the signal input in the following order: voltage channel A, auxiliary voltage chan-
nel, current channel A, ground current channel. The first available signal is used for frequency calculation.
GE Multilin
setting selects the minimum per unit voltage or current level required to allow the underfre-
AND
SETTING
UNDERFREQ 1
MIN VOLT / AMP:
≥
Minimum
Figure 5–81: UNDERFREQUENCY SCHEME LOGIC
OVERFREQUENCY
OVERFREQ 1 FUNCTION:
Disabled
OVERFREQ 1 BLOCK:
Off
OVERFREQ 1 SOURCE:
SRC 1
OVERFREQ 1 PICKUP:
60.50 Hz
OVERFREQ 1 PICKUP
DELAY: 0.500 s
OVERFREQ 1 RESET
DELAY : 0.500 s
OVERFREQ 1 TARGET:
Self-reset
OVERFREQ 1 EVENTS:
Disabled
F60 Feeder Protection System
SETTING
SETTING
UNDERFREQ 1
UNDERFREQ 1
PICKUP :
PICKUP DELAY :
RUN
UNDERFREQ 1
RESET DELAY :
t
≤ PKP
0 < f PICKUP
OVERFREQUENCY 1(4)
Range: Disabled, Enabled
Range: FlexLogic™ operand
Range: SRC 1, SRC 2
Range: 20.00 to 65.00 Hz in steps of 0.01
Range: 0.000 to 65.535 s in steps of 0.001
Range: 0.000 to 65.535 s in steps of 0.001
Range: Self-reset, Latched, Disabled
Range: Disabled, Enabled
5.6 CONTROL ELEMENTS
FLEXLOGIC OPERANDS
UNDERFREQ 1 PKP
UNDERFREQ 1 DPO
UNDERFREQ 1 OP
t
RST
827079A8.CDR
5.6.5 OVERFREQUENCY
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