5-194 L60 Line Phase Comparison System GE Multilin
5.5 GROUPED ELEMENTS 5 SETTINGS
5
The undervoltage delay setting defines the family of curves shown below.
(EQ 5.25)
where: T = operating time
D = undervoltage delay setting (D = 0.00 operates instantaneously)
V = secondary voltage applied to the relay
V
pickup
= pickup level
Figure 5–105: INVERSE TIME UNDERVOLTAGE CURVES
At 0% of pickup, the operating time equals the
UNDERVOLTAGE DELAY setting.
T
D
1
V
V
pickup
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⎝⎠
⎛⎞
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842788A1.CDR
% of voltage pickup
Time (seconds)