GE Multilin DFF, Инструкция по эксплуатации, Страница: 9 / 74

OPERATING PRINCIPLES
8 DFF Digital Feeder Relay GEK-106166E
2.1 PROTECTION FUNCTIONS
2.1.1 FREQUENCY UNITS
The DFF relay incorporates 8 underfrequency units. All frequency units are supervised by a voltage unit that inhibits
the frequency units in case the voltage decreases below the threshold.
The main settings for the frequency elements are:
GENERAL SETTINGS GROUP (Common to all Protection Functions of the relay)
Name Limits Default Step
RELAY STATUS
NO SERV / IN SERV NO SERV N/A
FREQUENCY 50 / 60 Hz 50 N/A
NOMINAL VOLTAGE 90 – 220 Vac 90 1
INHIBIT V
40 – 110 % 40 % 1
SEMICYCLES SET 3 – 20 3 1
SEMICYCLES RESET 0 – 4 0 1
PHASE VT RATIO
1 – 4000 1000 1
GROUND VT RATIO
1 – 4000 1000 1
SETTINGS FOR EACH INDIVIDUAL FREQUENCY ELEMENT (for example 81 N1)
Name Limits Default Step
FUNCTION TYPE FREQ. Or dF/dT FREQ. N/A
81 PICKUP 40.00 – 70.00 Hz 50 Hz 0.01 Hz
TIME DELAY
0.00 - 60.00 s 1.00 s 0.01 s
dF/dT -10.00 to -0.10 Hz/s - 0.75 Hz/s 0.01 Hz/s
RESET TIME 0.00 - 600.00 s 0.00 s 0.01 s
NOTE: The measuring resolution of the DFF equipment is always better than 5 mHz. However to avoid fluctuations
on the LCD display, the frequency is displayed in steps of 10 mHz. Measurements in 5 mHz steps are reflected on
the oscillogram.