GE Multilin L30 Line Current Differential System 5-199
5 SETTINGS 5.6 GROUPED ELEMENTS
5
The undervoltage delay setting defines the family of curves shown below.
(EQ 5.22)
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 5–82: 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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=
842788A1.CDR
% of voltage pickup
Time (seconds)