Basler Electric BE1-11t - Manual (Page 507)

9424200995 Rev H 495
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 304.
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
BE1-11t Time Curve Characteristics