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Async RS-232 DB25 Fallback (Failover) Switch

Complete disaster recovery, the RS232 Fallback Switches provide automatic backup.


4 In Stock
Same Day Shipping (before 5PM ET)
Extended Double Diamond™ Warranty Available (3 Additional Year)

*Required field

Product Features

  • Instantly detects lapses in the primary line, then switches to a backup line.
  • Use it as a line sharer with automatic flow control.
  • Front-panel LEDs show you system status at a glance.


Keep leased-line failures from costing you time and money. The instant the RS-232 Fallback Switch detects a lapse in the primary line, it switches your system to a backup line. As soon as signal is restored, it switches back to the primary line. The switch can support data rates as high as your RS-232 line can carry.

Tech Specs

CE Approval No
Connectors (3) DB25 F; master port is DCE, primary and alternate ports are DTE
Dimensions 2.3"H x 8.3"W x 11.5"D (5.8 x 21.1 x 29.2 cm)
Indicators (2) LEDs: ALT/PRI
Interface RS-232, synchronous or asynchronous
Leads Supported 2–6, 8, 15, 17, 20–22, 24; 1 and 7 tied common
Power 115/230 VAC, 60/50 Hz (switch-selectable), 8 watts
Switches (1) 3-position mode selector
Weight 2 lb. (0.9 kg)
All 12 required leads of the RS-232 interface for async or sync are switched.

* Technical specification weight is the unit weight. It is not the packaged shipping weight. For shipping weight, please contact Black Box customer service at 877-877-2269.



Double Diamond Warranty

Extended 1 Year Warranty Available

Protect your purchase with an additional 1 Year Double Diamond™ warranty!
Cost: $46.77

Extended 3 Year Warranty Available

Protect your purchase with an additional 3 Year Double Diamond™ warranty!
Cost: $93.53


Double Diamond™ Warranty (Standard)

Take the risk out of equipment purchases with the Double Diamond™ Warranty from Black Box Network Services.

The Double Diamond Warranty is our warranty that protects your Black Box® brand products* from accidental damage, including drops, water, and power surges.

The Async RS232 DB25 Fallback (Failover) Switch comes with a standard 1 Year Double Diamond™ Warranty (Standard) already included.

During the warranty period, Black Box Network Services will repair or replace your damaged equipment within one week of receipt at NO CHARGE!*

Plus, get an Extended Double Diamond Warranty.

You can also extend your warranty or protect a previously purchased Black Box® brand product** for an additional year—for only 10% of the purchase price! Or, extend your coverage for a full three years for only 20% of the purchase price!

Ordering an extended warranty is easy: When viewing a product in your shopping cart, just select the one or three years of additional coverage in the dropdown menu under “Warranty Options.” For details, contact Customer Service at 724-746-5500.

* Warranty subject to certain exclusions and limitations ** Certain products may not be eligible.

What’s more, we also have a 45-day return policy. Simply call Customer Service for a Return Authorization (RA) number, return your product in new condition and in the original package, and receive a full refund.