1
Make your system
more reliable by
switching to a backup
modem when your
primary link fails.
Minimize downtime
and inconvenience.
Flexible—can perform
either manual or
automatic changeover
switching.
Front-panel LEDs
show you system
status at a glance.
Supports rates as high
as your RS-232 line
can carry.
230-volt version
available.
B
reakdowns in your data
communication are always
inconvenient—and often
expensive. Our RS-232 Fallback
Switch gives you another way to
get your vital data through with
the least amount of downtime.
By diverting the traffic from
a primary modem to a backup
modem when the preferred
communications pathway fails,
the RS-232 Fallback Switch keeps
your data flowing. And because
the switchover is fast, efficient,
and highly reliable, you’re given
that extra bit of assurance that
your essential information will
be there when it needs to be.
Ideal for switching your data
from a dedicated leased-line
modem to a dialup modem when
the leased line goes down, the
device switches all 12 leads that
are normally required for sync or
async operation. What’s more, it
can support data rates as high as
your RS-232 cable can carry.
PRIMAR
Y
ALTERNA
TIVE
RS-232 F
ALLBACK SWITCH
PRI
AUT
O
ALT
End transmission downtime with
automatic modem switching.
Key Features
RS-232 FALLBACK SWITCH
Automatic or manual modes
The RS-232 Fallback Switch
also gives you several switching
options, providing flexibility as
your system requirements
change. You can operate the
switch manually (physically
switching between modems as
needed), but it also has two
automatic modes of operation:
normal fallback (FB) mode and
autoswitching (AS) mode, which
you can customize by setting
jumpers inside the unit.
Preset to operate in FB mode,
the switch normally
communicates with the modem
attached to its PRIMARY
connector. But, during automatic
operation, the RS-232 Fallback
Switch also checks constantly for
the presence of a “trigger signal”
on its ALTERNATE connector. And
if one is sensed—whether it’s
DSR (Data Set Ready, Pin 6), CTS
(Clear To Send), or Carrier Detect
(CD), depending on which of
these you select—it’ll switch to
the modem attached to that
connector. (This switch occurs
even if the primary modem is still
operating.) When the switch no
longer senses the trigger signal,
it “falls back” to the primary
modem.
In contrast, if you set the
switch’s jumper to AS mode,
the RS-232 Fallback Switch
doesn’t give either the primary or
alternate channel higher priority
than the other; it switches to
whichever modem raises the
trigger signal first, and won’t
switch back to the other modem
until the currently connected one
drops the trigger signal.
Simple to set up and operate
Once the switch is configured,
simply install it in a cool, dry place
close to the devices you want to
attach to it and connect the
necessary cables. This simple
Black Box Corporation
• 1000 Park Drive • Lawrence, PA 15055-1018 • Tech Support: 724-746-5500 •
www.blackbox.com
•
e-mail: [email protected]
© 2003. All rights reserved.
Black Box Corporation.
12/18/2003
#11110
