Schweitzer Engineering Laboratories SEL-487V, Руководство пользователя, Страница: 7 / 32

Schweitzer Engineering Laboratories, Inc. SEL-487V Data Sheet
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without a corresponding change in positive- or zero-
sequence current. Tests and field experience show that
this principle is very secure and is faster than the tripping
elements.
Faulted Phase and Section
Identification Logic
The SEL-487V makes sensitive measurements of the
magnitude and phase angle of differential quantities
generated by the failure of fuses or elements within the
capacitor bank. The SEL-487V uses these measurements
to automatically determine the faulted phase (A, B, C)
and section (top, bottom or left, right) in grounded and
ungrounded capacitor bank applications. The faulted
phase and section identification logic can be used to
provide local or remote indication of the problem area
within the capacitor bank so that fault location
identification times are reduced. The faulted phase and
section identification logic is processed each time a
differential alarm, trip, or high-set element asserts.
Six Independent Settings Groups
Increase Operation Flexibility
The relay stores six settings groups. Select the active
settings group by control input, command, or other
programmable conditions. These settings groups can
cover a wide range of control contingencies and
operating conditions. Selectable settings groups make the
SEL-487V ideal for applications requiring frequent
settings changes and for adapting to changing system
conditions.
Selecting a group also selects logic settings. Program
group logic to adjust settings for different operating
conditions, such as station maintenance, seasonal
operations, emergency contingencies, loading, source
changes, and adjacent relay settings changes.
Local Control
The SEL-487V provides dynamic one-line bay diagrams
on the front-panel screen with disconnect and breaker
control capabilities for predefined user-selectable bay
types. The relay is equipped to control as many as ten
disconnects and a single breaker, depending on the one-
line diagram selected. Operate disconnects and the
breaker with ASCII commands, SEL
OGIC
control
equations, Fast Operate messages, and from the one-line
diagram. The one-line diagram includes user-
configurable apparatus labels and as many as six user-
definable analog quantities.
One-Line Bay Diagrams
The SEL-487V offers a variety of preconfigured one-line
diagrams for common bus and capacitor bank
configurations. Once a one-line diagram is selected, the
user has the ability to customize the names for all of the
disconnect switches, capacitor bank, buses, and breaker.
Most one-line diagrams contain analog display points.
These display points can be set to any of the available
analog quantities with labels, units, and scaling. These
values are updated real-time along with the breakers and
switch position to give instant status and complete
control of a bay.
The operator can see all valuable information on a bay
before making a critical control decision. Programmable
interlocks help prevent operators from incorrectly
opening or closing switches or breakers. The SEL-487V
will not only prevent the operator from making an
incorrect control decision, but can notify and/or alarm
when an incorrect operation is initiated.
Circuit Breaker Operations From
the Front Panel
The one-line diagram is selectable from the Bay settings.
Additional settings for defining labels and analog
quantities are also found in the Bay settings of the relay.
One-line diagrams are composed of the following:
➤
Bay Names and Bay Labels
➤
Busbar and Busbar Labels
➤
Breaker and Breaker Labels
➤
Capacitor Bank Labels
➤
Disconnect Switches and Disconnect Switch
Labels
➤
Analog Display Points
Figure 6 shows the breaker control screens available
when the
ENT
pushbutton is pressed with the circuit
breaker highlighted as shown in Figure 6 (a). After
pressing the ENT pushbutton with the breaker highlighted
and the LOCAL Relay Word bit asserted, the breaker
control screen in
Figure 6 (b) is displayed. After entering
the screen in Figure 6 (b), the relay performs the circuit
breaker operations as outlined in the SEL-487V
Instruction Manual . If the LOCAL Relay Word bit is not
asserted when the
ENT
pushbutton is pressed, the screen
in Figure 6 (c) is displayed for three seconds, then the
relay displays again the screen in Figure 6 (a).