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5.17
Date Code 20171006
Instruction Manual
SEL-400 Series Relays
Control
Bay Control Front-Panel Operations
Single-Pole Tripping
With a single-pole breaker, the individual poles operate independently, and nor-
mal operation is for one pole to be open for a short period, while the other two
poles are closed. However, it is possible that one (or more) poles may fail to com-
plete a particular operation, resulting in a pole-discrepancy condition. For exam-
ple, if the breaker is issued a
CLOSE
command, two poles may close but one
pole may remain open. If this condition lasts for longer than 1.5 seconds, the
HMI displays the pole discrepancy screen shown in
so that the
operator can immediately identify the offending pole. You can operate the
breaker from the pole discrepancy screen after the discrepancy has been rectified.
All other screens are the same as when you set the relay to three-pole operations.
Figure 5.9
Screens for Circuit Breaker Selection
<BAYNAME>
<BAYNAME>
TRIP BREAKER
CLOSE BREAKER
STATUS
<BmCTLNM>
PRESS TO ACTIVATE
BAY not in
LOCAL Control!
Cannot issue
controls.
Press Enter with breaker
highlighted
Highlighted
(breaker
example)
(a) Bay Screen
(c) LOCAL bit NOT asserted
(b) Breaker Control Screen
If LOCAL
bit asserted
If LOCAL bit
NOT asserted
After message timeout,
screen (a) is displayed
m = S, T, U, W, X
<BAYNAME>
NAVIG
M. MENU
LV
I:99999A
V:99999kV
P:99999MW
Q:99999MW
HVBUSN1
HVBUSN2
<DmHMINM>
<BkHMINM>
<DmHMINM>
<DmHMINM>
<DmHMINM>
<DmHMINM>
Summary of Contents for SEL-421-4
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