Basler BE1-67N Instruction Manual Download

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3-2

BE1-67N Functional Description

9190700990 Rev F

Outputs from the sensing input transformers are applied to a scaling circuit that converts each of the input
currents to a dc voltage level. Scaling is controlled by the Tap Selector switch and the Tap Calibration
control on the front panel.

The Tap Selector switch is a 10-position rotary switch that controls the relay settings listed in Tables 3-2
and 3-3. The values of current listed are obtained with the Tap Calibration control adjusted fully
clockwise. Range is determined by the relay current sensing input connections. When the Tap Calibration
control is in the fully clockwise position, the relay pickup setting will be within

5% of the Tap Selector

switch setting.

Table 3-2. Sensing Input Range and Setting for 1 Aac Secondary

Tap Selector Switch Position

Nominal

Range

A B C D E F G H I J

Terminals

High 0.225 0.300 0.450 0.453 0.675 0.750 0.900 0.925 1.125 1.200 7

and

Low

0.075 0.100 0.150 0.175 0.225 0.250 0.300 0.325 0.375 0.400 7

and

Table 3-3. Sensing Input Range and Setting for 5 Aac Secondary

Tap Selector Switch Position

Nominal

Range

A B C D E F G H I J

Terminals

High 1.125 1.500 2.250 2.625 3.375 3.750 4.500 4.875 5.625 6.000 7

and

Low

0.375 0.500 0.750 0.875 1.125 1.250 1.500 1.625 1.875 2.000 7

and

The Tap Calibration control provides continuous adjustment between a selected setting of the Tap
Selector switch and the next lower setting. When the Tap Calibration control is adjusted fully clockwise,
the relay pickup setting will be within

5% of the Tap Selector switch setting.

VOLTAGE SENSING

The relay receives a polarized voltage input (V

) from the secondary windings of standard potential

transformers or coupling capacitor potential devices. These components supply up to 240 volts (line to
neutral) for a 50/60 hertz nominal system frequency.

DIRECTIONAL ELEMENT

The directional element determines when the monitored power system quantities have the proper phase
relationship for tripping. The BE1-67N has three types of switch-selectable, directional capabilities: zero
sequence current polarization, zero sequence voltage polarization, and dual zero sequence current and
voltage polarization. Polarizing Source Select Switch S3, located on the Analog circuit board, is used to
select the desired directional capability.

Zero Sequence Current Polarization

The zero sequence current polarizing unit is capable of detecting the phase relationship between the zero
sequence current (I

) and the sensed, measured current (I

) for the relay. This unit is insensitive to third

and higher harmonics.

An enabling output from the zero sequence current unit is given when the phase angle between I

and I

is 75

or less as shown in Figure 3-2. The total trip region (shaded area in Figures 3-2, 3-3, and 3-4) is

150

To allow operation of the time overcurrent element, the level of I

applied to the directional element must

be in excess of 0.2 amperes.

To allow operation of the directional instantaneous overcurrent element, the level of I

applied to the

directional element must be in excess of an internal, user adjustable threshold. The range of this setting is
0.75 to 2 amperes. The default, factory setting is 2 amperes.