CHAPTER 5: SETTINGS
5.8.5 Underfrequency (ANSI 81U)
SETTINGS CONTROL ELEMENTS UNDERFREQUENCY UNDERFREQUENCY 1(6)
UNDERFREQUENCY 1
There are six identical underfrequency elements, numbered 1 through 6.
D30 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 5-153: Selector switch logic
UNDFREQ 1 FUNCTION:
Disabled
UNDERFREQ 1 BLOCK:
Off
UNDERFREQ 1 SOURCE:
SRC 1
UNDERFREQ 1 MIN
VOLT/AMP: 0.10 pu
UNDERFREQ 1 PICKUP:
59.50 Hz
UNDERFREQ 1 PICKUP
DELAY: 2.000 s
UNDERFREQ 1 RESET
DELAY : 2.000 s
UNDERFREQ 1 TARGET:
Self-reset
UNDERFREQ 1 EVENTS:
Disabled
Range: Disabled, Enabled
Range: FlexLogic operand
Range: SRC 1, SRC 2
Range: 0.10 to 1.25 pu in steps of 0.01
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
CONTROL ELEMENTS
5
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