Under/Overvoltage (27/59) - Basler BE1-11g Instruction Manual

9424200994 Rev U

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 42. The undervoltage inverse time curve with
default constants is shown in Figure 378.
= Time to trip when M ≥ 1
T
T
= Time to reset if BE1-11g is set for integrating reset when M < 1. Otherwise, reset is
T
R
50 milliseconds or less
D = Time Dial setting (0.0 to 9.9)
M = Multiple of Pickup setting
A, B, C, N = Constants for the particular curve
R = Constant defining the reset time.
BE1-11g
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Equation 42
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Equation 43
631
Time Curve Characteristics