Schweitzer Engineering SEL-2032, Instruction Manual

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7.9
Date Code 20120126 Instruction Manual SEL-2032 Communications Processor
Settings
Port Configuration (SET P) and Communication Settings
channel idle time (set with TERTIME2). All of these items are user definable
and can be set such that they are not used when less security is required. The
SEL-2032 default termination sequence has the first time delay set to one
second, the termination character set to <EOT> (end of transmission
character, ASCII character 4,
<Ctrl+D> on most keyboards), and the second
time delay set to zero.
Direct
Transparent Mode
The SEL-2032 normally uses data buffering when transferring data through
transparently connected ports. Some non-SEL IED protocols are intolerant of
this data buffering since the buffering introduces random inter-character time
delays into the data stream. The SEL-2032 includes a Direct Transparent
mode that eliminates these inter-character delays while maintaining the
buffering effectiveness. The Direct Transparent mode inter-character delay is
typically less than one millisecond and never exceeds two milliseconds. The
Direct Transparent mode is available on any rear-panel Master port, however
is not available on the front Master port.
To select the Direct Transparent mode, add the D parameter to the PORT
command ( PORT n D , where n selects the port number). The SEL-2032
passes characters through rapidly, without significant buffering delays.
Therefore, no handshaking is required if the Master and Slave port baud rates
match. Hardware handshaking may be required if the Master and Slave port
baud rates do not match. Software handshaking (XON/XOFF) is not
supported by the SEL-2032 in Direct Transparent mode, regardless of the
XON_XOFF port setting. However, XON/XOFF characters pass through the
transparent port connection, allowing the connected devices to use software
handshaking independent of the SEL-2032.
The Direct Transparent mode (D parameter) typically should not be used
when transparently connecting to SEL devices. SEL interleaved binary
messages (binary 20METER, 20TARGET, etc.) are not supported during
Direct Transparent mode connections.
Virtual Terminal
Communications
The SEL-2032 supports virtual terminal (VT) communications when a VT-
enabled card is installed in Port 17 or Port 18. VT support allows a user to
communicate using ASCII commands through a network, similar to directly
communicating via an ASCII terminal.
The SEL-2032 can function as a VT server. For example, with an SEL-2701
Ethernet Processor installed in an SEL-2032, a user located at a PC connected
to the Ethernet network can communicate with the SEL-2032. The virtual
terminal mechanism for Ethernet is Telnet. At the PC, using Telnet client
software, the user specifies the information to establish a connection with the
SEL-2032. At this point, the keyboard and Telnet window on the PC emulate a
direct ASCII terminal link to the SEL-2032.
The SEL-2032 can also function as a VT client. This is a special case of the
transparent communications, initiated by a
PORT command from a terminal
connected to an SEL-2032 master port. The user specifies a network port with
VT capability and a network destination address. For example, with a laptop
PC connected to the front port of an SEL-2032, a user can establish a Telnet
connection through an SEL-2701 and Ethernet to a relay located in another
station. For example, use the command
PORT 17 10.200.0.53 to connect to
the device with IP address 10.200.0.53.
Courtesy of NationalSwitchgear.com