4.13
Date Code 20170601
Instruction Manual
SEL-387-0, -5, -6 Relay
Control Logic
Rotating Default Display
Rotating Default Display
The rotating default display on the relay front panel replaces indicating panel
lights. Traditional indicating panel lights are turned on and off by circuit
breaker auxiliary contacts, front-panel switches, SCADA contacts, etc. See
Section 8: Front-Panel Interface
for details.
LED Targeting Logic
The SEL-387 has 16 LEDs on the front panel. One (
EN
) is dedicated to
indication of the relay operational condition. Twelve are dedicated to specific
targeting functions. Three (
LEDA
,
LEDB
, and
LEDC
) have default targeting logic
but are fully programmable by the user.
The states of the 12 dedicated LEDs (all but
EN
,
A
,
B
,
C
) are stored in
nonvolatile memory. If power is lost to the relay, these 12 targets will be
restored to their last state when the relay power is restored.
EN
responds only
to internal self-test routines, while
A
,
B
, and
C
respond to the present state of
their respective Global SEL
OGIC
control equation settings.
The array of LEDs is shown below in
.
Figure 4.6
SEL-387 Front-Panel LEDs
describes the basic targeting functions associated with each of the 16
LEDs.
Table 4.6
LED Assignments
(Sheet 1 of 2)
LED
Legend
Description
1
EN
Relay enabled
2
TRIP
a
Relay trip
3
INST
Instantaneous trip
4
87-1
Differential element 1 asserted at, or 1 cycle after, rising edge of trip
5
87-2
Differential element 2 asserted at, or 1 cycle after, rising edge of trip
6
87-3
Differential element 3 asserted at, or 1 cycle after, rising edge of trip
7
50
Instantaneous O/C element asserted at, or 1 cycle after, rising edge of
trip
8
51
Time O/C element asserted at, or 1 cycle after, rising edge of trip
9
A
A-phase involved in the fault (Programmable LEDA)
10
B
B-phase involved in the fault (Programmable LEDB)
11
C
C-phase involved in the fault (Programmable LEDC)
OVERCURRENT
FAULT TYPE
A
B
C
N
W1
W2
W3
TRIP
EN
DIFFERENTIAL
INST
87-1
87-3
87-2
50
W4
51
Summary of Contents for SEL-387-0
Page 6: ...This page intentionally left blank ...
Page 12: ...This page intentionally left blank ...
Page 50: ...This page intentionally left blank ...
Page 200: ...This page intentionally left blank ...
Page 248: ...This page intentionally left blank ...
Page 380: ...This page intentionally left blank ...
Page 422: ...This page intentionally left blank ...
Page 440: ...This page intentionally left blank ...
Page 458: ...This page intentionally left blank ...
Page 516: ...This page intentionally left blank ...