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Catalog # 307387 - Model 7387 DB25 A/B Switch with Fallback

    DB25 A/B Switch with FallbackDB25 A/B Switch with FallbackDB25 A/B Switch with FallbackDB25 A/B Switch with Fallback
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    • DB25 A/B Switch with Fallback
    • DB25 A/B Switch with Fallback
    • DB25 A/B Switch with Fallback
    • DB25 A/B Switch with Fallback
Base Price:
Catalog No: 307387
Model No: 7387
Product Type:Switches: Copper
Cable Type/Port Connector:DB25 Switch Ports
Channels per Switch Chassis:1
Electronic Switches/Power Required:PathWay® Copper
Remote Control:Auto Fallback, Contact Closure
Auto Fallback:RD & DCD Monitor Port A & Port B
Pins Switched:All pins of DB25
Remote Port:DB15
Local Control:Pushbutton


Shipping Terms

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Products shall be shipped F.O.B. Electro Standards' facility. Title to and risk of loss or damage to the products shall pass to you upon Electro Standards delivery of the products to a carrier for shipment. Title to software will remain with the applicable licensor. Electro Standards' prices do not include shipping and handling charges. Electro Standards reserves the right to use its own discretion in the manner and routing of shipments. Electro Standards shall be permitted to deliver products in separate lots.

Shipping Return Policy

  • To return an item, contact Electro Standards at 401-943-1164 to obtain a Return Material Authorization (RMA) number. RMA numbers are valid for 30 days after the date of the shipment and cannot be extended or re-issued. We are unable to accept returns without an RMA number.
  • All returns except those of defective product are subject to a 15% restocking fee, and additional charges for handling or freight are refunded only in cases of defective products.
  • Return freight must be shipped prepaid. We recommend that you insure the package as you are responsible for risk of loss on all returned packages. We recommend that all cartons are properly packed as Electro Standards is not responsible for product damaged en route. We do not issue call tags for product returns.
  • Returned product must be clean, undamaged, and complete with all manuals, accessories, documents and packaging. The items must be in a resalable condition.
  • The product must have with it a copy of the original invoice or packing slip and the appropriate RMA paperwork.
  • If your item is not working properly, please contact Electro Standards at 401-943-1164 for help in trouble-shooting your application.
  • If the product is defective, Electro Standards will repair or replace that item (at our discretion) upon receipt and evaluation of the original product.
  • Electro Standards reserves the right to authorize product returns after 30 days from the invoice date in some cases. If the product is accepted after 30 days, credit will be issued toward future pruchases only and some additional restocking charges may be applied.
  • All credits from RMAs must be used within one calendar year of issue.

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Model 7387 Single Channel RS232 DB25 A/B Switch with Fallback and Remote Port

  • Can also switch automatically.  You select the trigger signal: RD or DCD


  • PORT CONNECTORS: (3) DB25 female connectors labeled A, B, and Common.
  • FRONT PANEL CONTROL: (1) manual pushbutton allows local switching.
  • DISPLAY: (2) Front panel LED's display switch position, power status
  • and mode of operation.
  • REMOTE CONTROL: (1) DB15 female connector on rear panel accepts Contact Closure for Remote Control Operation.
  • POWER:  UL approved 100VAC/240VAC, 50Hz/60 Hz wall mount power module supplies 12 VDC, 500mA to the unit. Has 2-prong, US, non-polarized plug. (Cat. No. 516682) 
  • DIMENSIONS: Rackmount, 19.0" W x 1.75" H x 8.0" D. [48.3 x 4.5 x 20.9 cm]
  • WEIGHT: Approximately 4.3 lbs [2.0 kg] 

 PathWay® Model 7387 RS232 DB25 A/B Switch Application:

PathWay® Model 7387 RS232 DB A/B Application w/Fallback Mode and a Remote port: The drawing illustrates a DB15 A/B Auto Fallback Switch based on Data Activity Trigger and Data Carrier Trigger. A Device connected to the COMMON port has access to two devices connected to the DB25 A and B ports. The DB15 Remote port is a Contact Closure and Status port for remote control.

PathWay Model 7387 RS232 A/B Switch Application


  • The unit may be switched manually, remotely, or automatically.
  • The switch ports are transparent to all data.
  • All 25 pins of the DB25 interface are switched via break-before-make electromechanical relays.
  • Protective ground Pin 1 is tied together between A, B and COM.
  • Signal ground Pin 7 on A and B are tied to board ground for reference when monitoring signals.
  • All switched signals are passed via latching copper contact relays that maintain their position and continuity even in the event of power loss or failure.
  • When power is restored, unit loads previous position and mode of operation and checks DIP switch settings and Remote port to determine the correct startup configuration.
  • Remote Contact Closure control and status provides dry contact logic to allow the control of switch position, as well as obtain the present position.
  • Front panel LED's display switch position, mode and power status.
  • Municipalities, schools, government: This product is on GSA Schedule!  

The PathWay® Model 7387 Single Channel RS232 DB25 A/B Switch with Fallback and Remote Port allows the user the capability of sharing a single port interface device connected to the “COMMON” port among two other devices connected to the “A” and “B” ports with remote access functionality.  The Remote port can be used to attain switch position status by using the provided set of Contact Closure pins.  The Remote port can also be used to control the switch position using a separate set of Contact Closure pins.  The Model 7387 is enclosed in a 1U, full rack size, all metal black chassis designed to provide EMI/RFI shielding and fit in a standard 19” rack. 

When in Automatic Fallback Mode, the unit monitors either RD activity or DCD presence on ports A and B.  If activity or presence is lost on the active port, the unit checks if there is activity or presence on the other port and, in the event, that there is activity or presence, the unit switches to the other port.  If there is no activity or presence on either port, the unit will maintain its connection to its present port and continue to monitor both ports.  The user can override Automatic Fallback operation from the front panel or Remote port and force the unit to operate as an A/B switch.

Option: Wide Range Power Module: (Cat No. 517277) CE, RoHS and UL listed table mount power module, 100VAC/240VAC, 50Hz/60Hz in place of the standard power module that is included with the unit.  Has IEC 60320 C14 inlet.  Ideal for international applications.

This high-quality network switch is available to city, state, and federal government purchasers at a discounted price and favorable payment and shipping terms via GSA Schedule GS-35F-0286V. Click here or on GSA icon for details.

TO READ THE ARTICLE: "ADVANCES IN NETWORK SWITCHES",  click link to read as a pdf. You need Acrobat Reader to view this file. 

This high-quality network switch is available to city, state, and federal government purchasers at a discounted price and favorable payment and shipping terms via GSA Schedule GS-35F-0286V. Click here for GSA details.

Electro Standards can supply all your Network Cable requirements. Click here to reach our CABLES, COPPER NETWORK Webpage.

For custom network switches call our friendly customer support staff at 401-943-1164, email eslab@electrostandards.com, or complete our online form: /Products-Custom/Copper-Switch/

All data switches, data communication products, and data acquisition products are subject to a one year warranty against manufacturing defects.  The limit of ESL liability is limited to the cost of the ESL product provided.

*Prices online are subject to change and verification.

All ESL products are available for export.

Electro Standards welcomes International inquiries: commutateur d'ordinateur,  equipo interruptor, interruttore del calcolatore, interruptor do computador, dator switch.

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