Date Code 20171021 Instruction Manual SEL-421 Relay
Instruction ManualInstruction Manual
SECTION 9
ASCII Command Reference
You can use a communications terminal or terminal emulation program to set and
operate the SEL-421 Relay. This section explains the commands that you send to
the SEL-421 using SEL ASCII communications protocol. The relay responds to
commands such as settings, metering, and control operations.
This section lists all the commands supported by the relay but most are described
in Section 14: ASCII Command Reference in the SEL-400 Series Relays Instruc-
tion Manual. This section provides information on commands and command
options that are unique to the SEL-421.
This section lists ASCII commands alphabetically. Commands, command
options, and command variables that you enter are shown in bold. Lower case
italic letters and words in a command represent command variables that you
determine based on the application (for example, circuit breaker number
n = 1 or 2, remote bit number nn = 01–32, and level).
Command options appear with brief explanations about the command function.
Refer to the references listed with the commands for more information on the
relay function corresponding to the command or examples of the relay response
to the command.
You can simplify the task of entering commands by shortening any ASCII com-
mand to the first three characters; for example, ACCESS becomes ACC. Always
send a carriage return <CR> character, or a carriage return character followed by
a line feed character <CR><LF> to command the relay to process the ASCII
command. Usually, most terminals and terminal programs interpret the <Enter>
key as a <CR>. For example, to send the ACCESS command, type ACC
<Enter>.
Tables in this section show the access level(s) where the command or command
option is active. Access levels in the SEL-421 are Access Level 0, Access
Level 1, Access Level B (breaker), Access Level P (protection), Access Level A
(automation), Access Level O (output), and Access Level 2.
To Next Page
Loading...
