FEATURES
• Fast to install, easy to manage.
• Manageable through your Web browser.
• Compact size.
• Supports RS-232, RS-422, and RS-485.
• RoHS compliant.
OVERVIEW
The RS-232/422/485 Device Server is a quick and easy way
to connect to an RS-232/422/485 serial device across your
network. There’s no need to run separate serial cable, and
there are no distance limitations—anywhere your network
goes, you can make a serial connection. Use the device server
to access faraway serial devices such as printers, scanners,
and industrial devices. And, because the device server accepts
AT commands, you can even use it as a modem substitute,
replacing a pair of modems and a phone line with a pair of
device servers and your Ethernet network—a very economical
solution for legacy devices that communicate by modem.
Operation is transparent to your equipment and your
software. The device server encapsulates serial data into
packets for transport over Ethernet. Another device server
takes the data from the Ethernet side and turns it back into
serial data.
The device server features a built-in Web server so you
can access its management features from your PC using
any standard Web browser. You can also manage it locally
through the serial port or by using Telnet™. The device server
also includes Windows®based configuration software.
Item Code
RS-232/422/485 Device Server LES290A
TECH SPECS
Data Rate — Ethernet: 10/100 Mbps, autosensing or software selectable;
Serial: 300 bps to 230 kbps, software selectable
Management — Included Windows based configuration software, serial
login, SNMP, Telnet login, HTTP
Serial Interface — RS-232, RS-422, or RS-485, software selectable; 7 or 8
data bits; even, odd, or no parity; 1 or 2 stop bits; CTS/RTS; X-ON/X-OFF
Standards — IEEE 802.3, IEEE 802.3u, ARP, UDP, TCP, ICMP, Telnet, TFTP,
AutoIP, DHCP, HTTP, SNMP
CE Approval — Yes
Connectors — (1) RJ-45, (1) DB25 F
Indicators — LEDs: (1) Power, (1) Link/Activity, (1) Status
Environmental — Operating temperature: 41 to 122°F (5 to 50°C);
Storage temperature: -40 to +151°F (-40 to +66°C)
Power — 100–240 VAC, 50–60 Hz external power supply
Size — 0.9"H x 2.5"W x 3.5"D (2.3 x 6.4 x 9 cm)
Terminal servers.
A terminal server (sometimes called a serial server or a
console server or a device server) is a hardware device that
enables you to connect serial devices across a network.
Terminal servers acquired their name because they
were originally used for long-distance connection of dumb
terminals to large mainframe systems such as VAX™. Today,
the name terminal server refers to a device that connects any
serial device to a network, usually Ethernet. In this day of
network-ready devices, terminal servers are not as common
as they used to be, but they’re still frequently used for
applications such as remote connection of PLCs, sensors, or
automatic teller machines.
The primary advantage of terminal servers is that they save
you the cost of running separate RS-232 devices. By using a
network, you can connect serial devices even over very long
distances—as far as your network stretches. It’s even possible
to connect serial devices across the Internet. A terminal server
connects the remote serial device to the network, and then
another terminal server somewhere else on the network
connects to the other serial device.
Terminal servers act as virtual serial ports by providing
the appropriate connectors for serial data and also by
grouping serial data in both directions into Ethernet TCP/IP
packets. This conversion enables you to connect serial devices
across Ethernet without the need for software changes.
Because terminal servers send data across a network,
security is a consideration. If your network is isolated, you
can get by with an inexpensive terminal server that has few or
no security functions. But if you’re using a terminal server to
make network connections across a network that’s also an
Internet subnet, you should look for a terminal server that
offers extensive security features.
Technically Speaking
