4.122
SEL-751A Relay
Instruction Manual
Date Code 20100129
Protection and Logic Functions
Report Settings (SET R Command)
Report Settings (SET R Command)
The report settings use Relay Word bits for the SER trigger as shown in
for more information).
SER Chatter Criteria
The SER includes an automatic deletion and reinsertion function to prevent
overfilling of the SER buffer with chattering information. Each processing
interval the relay checks the Relay Word bits in the four SER reports for any
changes of state. When detecting a change of state, the relay adds a record to
the SER report containing the Relay Word bit(s), new state, time stamp, and
checksum (see
for more information).
When detecting oscillating SER items, the relay automatically deletes these
oscillating items from SER recording.
shows the auto-removal
settings.
To use the automatic deletion and reinsertion function, proceed with the
following steps:
Step 1. Set Report setting ESERDEL (Enable SER Delete) to Y to
enable this function.
Step 2. Select values for the setting SRDLCNT (SER Delete Count)
and the setting SRDLTIM (SER Delete Time) that mask the
chattering SER element.
Setting SRDLTIM declares a time interval during which the relay qualifies an
input by comparing the changes of state of each input against the SRDLCNT
setting. When an item changes state more than SRDLCNT times in an
SRDLTIM interval, the relay automatically removes these Relay Word bits
from SER recording. Once deleted from recording, the item(s) will be ignored
for the next nine intervals. At the ninth interval, the chatter criteria will again
be checked and, if the point does not exceed the criteria, it will be
automatically reinserted into recording at the starting of the tenth interval. The
user can enable or disable the auto-deletion function via the SER settings. Any
auto-deletion notice entry will be lost during changes of settings. The deleted
items can be viewed in the SER Delete Report (command
SER D
—refer to
for additional information).
PB4A_LED EQUATION
SEL
OGIC
PB4A_LED := 0
PB4B_LED EQUATION
SEL
OGIC
PB4B_LED := NOT 52A OR SV04 AND
NOT SV04T AND SV05T
Table 4.67
Pushbutton LED Settings
(Sheet 2 of 2)
Setting Prompt
Setting Range
Setting Name :=
Factory Default
Table 4.68
Auto-Removal Settings
Settings Prompt
Setting Range
Factory Default
Auto-Removal Enable
Y, N
ESERDEL := N
Number of Counts
2–20 counts
SRDLCNT := 5
Removal Time
0.1–90.0 seconds
SRDLTIM := 1.0
Summary of Contents for 751A
Page 1: ...20100129 SEL 751A Feeder Protection Relay Instruction Manual PM751A 01 NB...
Page 6: ...This page intentionally left blank...
Page 12: ...This page intentionally left blank...
Page 18: ...This page intentionally left blank...
Page 26: ...This page intentionally left blank...
Page 92: ...This page intentionally left blank...
Page 218: ...This page intentionally left blank...
Page 250: ...This page intentionally left blank...
Page 376: ...This page intentionally left blank...
Page 392: ...This page intentionally left blank...
Page 408: ...This page intentionally left blank...
Page 418: ...This page intentionally left blank...
Page 434: ...This page intentionally left blank...
Page 462: ...This page intentionally left blank...
Page 544: ...This page intentionally left blank...
Page 580: ...This page intentionally left blank...
Page 584: ...This page intentionally left blank...
Page 632: ...This page intentionally left blank...
Page 636: ...This page intentionally left blank...
Page 640: ...This page intentionally left blank...