Basler Electric BE1-11m - Manual (Page 499)

9424200996 Rev L 487
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 33 and shown in Figure 310.
𝑇
𝑇
=
𝐷
1 − �𝑉 𝑚
𝑉
𝑝𝑢
�
Equation 33. Undervoltage (27) Inverse Time Curve Definition
where:
T
T
= Time to Trip
D = Time Dial
V
m
= Measured Voltage
V
pu
= Voltage Pickup Setting
BE1-11m Time Curve Characteristics