Sel SEL-787 - Figure 4.42 Volts;Hertz Inverse-Time Characteristic, 24 IC = 2

4.57
Date Code 20150130 Instruction Manual SEL-787 Relay
Protection and Logic Functions
Voltage-Based Protection
Figure 4.42 Volts/Hertz Inverse-Time Characteristic, 24IC = 2
t
p
24ITD
VPP PTR
freq
-----------------------------
FNOM
VNOM 10
3

---------------------------------

24IP
100
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---------------------------------------------------------------------






1–







2.0
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seconds=
if V/Hz 1.5 24IP
t
p
4.0 24ITD seconds=
if V/Hz 1.5 24IP