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Catalog # 304503 - Model 4503 Vibration-Proof DB9 2-Position Switch

    Vibration-Proof DB9 2-Position SwitchVibration-Proof DB9 2-Position Switch
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    • Vibration-Proof DB9 2-Position Switch
    • Vibration-Proof DB9 2-Position Switch
Base Price:
Catalog No: 304503
Model No: 4503 DB9 2-Position Switch
Product Type:Switches: Copper
Cable Type/Port Connector:DB9 Switch Ports
Channels per Switch Chassis:1
Manual Control/No Power Required:LineSelect® Manual Operation
Pins Switched:9
Local Control:Rotary Knob

  • Ruggedized to withstand Environmental Challenges

  • Designed to pass rigorous seismic testing for use in nuclear power plants

  • DB9 A/B Switch with front panel Keylock


Shipping Terms

Shipments are made via UPS Ground, unless otherwise specified. Freight charges are prepaid and added to your invoice. We can estimate the freight costs for you.

We can ship freight collect on your account, just provide your UPS Account Number.

We can also ship via the carrier of your choice. Provide the details and your account number.

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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DB9 Manual Network Switch, Keylock Switch
LineSelect®Model 4503 Seismic-Proof DB9 A/B Data Network Switch

  • Ruggedized to withstand Environmental Challenges

  • Designed to pass rigorous seismic testing for use in nuclear power plants


  • CONNECTORS: A, B, COM are DB9 female connectors, located on rear panel.
  • CONTROL: Two position rotary switch control located on the front panel.
  • POWER: No power required. Manually operated.
  • Keylock pass-key switch control is optional.
  • DESKTOP SIZE: 4.18" W x 6" D x 1.75" H (10.6 x 15.2 x 4.4 cm)
  • 1/4 WIDTH RACKMOUNT SIZE: 6.4" W x 6" D x 1.75" (1U) H (16.5 x 15.2 x 4.4 cm)
  • WEIGHT: Approx. 2.0 lbs. (0.9 kg)

LineSelect® Model 4503 Switch Function:

The Switch Function shows a COMMON Device connected to the DB9 port with access to Device A or Device B by a turn of a front Panel Keylock.

LineSelect Model 4503 DB9  A/B Switch Function


  • All 9 pins are switched via break-before-make rotary switch.
  • Ruggedized to withstand vibrations.
  • Switch and options have passed rigorous seismic testing.
  • The Model 4503 DB9 A/B switch is ideal for power plant applications.
  • Rugged all-aluminum enclosure provides EMI/RFI resistance in noisy environments.
    • Optional "pass-key only" access ensures proper authorized usage (Catalog No. 304503-Opt-1)
    • Optional "mounting ears" allow firm attachment (Model No. 2959, Catalog No. 512959).
    • Optional accessory "feed-through" connector (Catalog No. 513904, DB-9 F/F Adaptor Plate.)
  • Manual data network switch, no power required
  • Lifetime guarantee against manufacturing defects!
  • Municipalities, schools, government: This product is on GSA Schedule!

The LineSelect® Model 4503 manual network switch was designed to withstand an environment subject to vibrations. This switch and its feed-through connector have successfully passed the rigorous seismic testing of the EPRI "SQURTS" Program, qualifying it for use in nuclear power plants. Model 4503 is ideal for factory floors, energy facilities, or any other harsh environment application.

The LineSelect® Model 4503 allows data to pass through all pins of the DB9/F connector interface and switches all pins simultaneously. The Keylock Option provides "pass-key only" access to switching. Key is captive in B position and removable in A position. LineSelect® Model 4503 manual network switch is available with mounting ears to secure it to a panel. It is also available in rackmount or desktop version.

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.

Model 4503 is available to government purchasers on our GSA Schedule GS-35F-0286V. Call for discounted price and terms.

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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