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Under/overvoltage (27/59), Undervoltage (27) inverse time curve – Basler Electric BE1-11g User Manual

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Under/Overvoltage (27/59)

The 27 and 59 elements have independent user defined definite and inverse time delays. The inverse
time curves are defined below.

Undervoltage (27) Inverse Time Curve

The undervoltage inverse time curve is defined by Equation 34 and shown in Figure 357.

𝑇

𝑇

=

𝐷

1 − �𝑉

𝑚

𝑉

𝑝𝑢

Equation 34. Undervoltage (27) Inverse Time Curve Definition


where:

T

T

= Time to Trip

D

= Time Dial

V

m

= Measured Voltage

V

pu

= Voltage Pickup Setting

BE1-11g

Time Curve Characteristics