Basler BE1-67, Instruction Manual, Page: 18 / 73

1-12 General Information BE1-67
Figure 1-11. Characteristic Angle
Pickup Accuracy
The setting of the relay is repeatable within ±2 percent.
Dropout Ratio
The dropout ratio is better than 92 percent of the established pickup level.
Voltage Sensing Inputs
The continuous rating of these inputs are 240 Vac.
Voltage Sensing Burden
The voltage sensing burden is greater than 25 kilo-ohm at 120 Vac per input.
Directional Unit
The polarizing for the directional unit is derived by the phase relationship between the measured phase current
(A) and the sensed quadrature voltage (b-c). The directional element defines a region as shown in Figure 1-11
for which tripping will be allowed. The characteristic angle of the relay is defined as the angle between I
z
and
its ordinate, I. Note that I
z
is normal to the characteristic boundary. Resolution of direction requires less than
1 cycle.
Sensitivity
Proper directional decisions are assured when the current applied to the relay exceeds 25% of TAP value and
the voltage exceeds 1.0 Vac at the setting of the characteristic angle. When polarizing voltage is less than the
1.0 Vac threshold, relay operation will be inhibited.
Characteristic Angle
Adjustment
The BE1-67 is available with two types of adjustment for the characteristic angle.