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Model 4172 Very High Speed Fiber to Multi-Point RS485/422 Interface Converter, Catalog #304172

    Fiber485® to Multi-Point RS485/422 Interface ConverterFiber485® to Multi-Point RS485/422 Interface ConverterFiber485® to Multi-Point RS485/422 Interface ConverterFiber485® to Multi-Point RS485/422 Interface Converter
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    • Fiber485® to Multi-Point RS485/422 Interface Converter
    • Fiber485® to Multi-Point RS485/422 Interface Converter
    • Fiber485® to Multi-Point RS485/422 Interface Converter
    • Fiber485® to Multi-Point RS485/422 Interface Converter
Base Price:
Catalog No: 304172
Model No: 4172
Product Type:Interface Converter
Converter Port Connector:DB9, ST
Conversion Type:Glass Fiber, RS422, RS485
Speed:RS485/422: 0 to 5 Mbps
Wavelength Nano:820 nm/850 nm, multimode


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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Interface Converters, ST Duplex Fiber, Multi-Point RS485/422
Fiber485® Model 4172 Very High Speed Ruggedized ST Duplex Fiber-to-Multi-Point RS485/422 Interface Converter

  • Ideal for RS485 Multi-Point Applications and Communications to Remote Sites

 The Model 4172 is a high speed ruggedized ST Duplex Fiber to RS485 / RS422 interface converter from Electro Standards Laboratories.  Typical operating speeds are up to 5 Mbps for RS485/422 to fiber conversion.  When operating in RS485/422 mode, the converter can be configured for 2-wire half duplex or 4-wire full duplex operation.

This Fiber to RS converter provides an industrial solution for applications requiring a single point-to-point or a multi-point communications link over short and long distances.  Typical applications include PC to PC long distance communications, factory automation, multi-drop data collection devices, barcode readers, time clocks, scales, data entry terminals, ATMs, toll booths and serial communications in harsh environments.

The Model 4172 Fiber to Multi-Point Converter is designed to operate from -40°C to 85°C and is a member of Electro Standards Laboratories rugged community of media converters.  This Fiber to RS converter features ESD protection circuitry on all receivers and transmitters for RS485/422 interfaces.  The unit's power input is protected from transients and features 3kVDC isolation to prevent system ground loops.  The Model 4172 media converter can be powered from a wide input range of 10VDC-36VDC, with models also available for other voltage ranges such as 4.5VDC-9VDC and 19VDC-72VDC.

Other features include user selectable fiber polarity and, also TX, RX and Power indicator LEDs. 


Fiber Interface:

  • Connectors: Fiber Optic ST Duplex
  • TX Power: -12.5 dBm
  • RX Sensitivity: -27.5 dBm
  • Optical Budget: 15 dB
  • Max. Link Distance with 62.5/125µm fiber:
  • 5.35 kM at up to 5 Mbps, 25°C
  • 3.75 kM at up to 5 Mbps, -40°C to 85°C
  • Wavelength: 820 nm/850 nm, multimode
  • Fiber Size: 50/125 µm, 62.5/125 µm, 100/140 µm.

Fiber Polarity:

  • Logical 1 = Light ON/OFF: Jumper Selectable

Copper Interface:

  • Connectors: DB9, Female
  • RS485 (2-wire/4-wire)
  • Terminations: RS485 120 Ohm jumper selectable

Bit Rate (nom.):

  • RS485/422: 0 to 5 Mbps

Network Configurations:

  • RS485/422Point-to-Point
  • Multi-Point (Default ~280 uSec TX disable time) (user configurable TX disable time via a single thru-hole resistor)




  • Input Power: 10VDC-36VDC std, 4.5VDC-9VDC, 19VDC-72VDC, Others at 1.5W.
  • Isolation: 3 kVDC

Operating Environment:

  • -40°C to 85°C

Model 4172 Mechanical (Desktop Unit):

  • Model / Cat No: 4172 / 304172
  • Size: 5" x 4.25" x 1.4"
  • Weight: 10.1 oz (286g)

Very High Speed Ruggedized ST Duplex Fiber to RS485/RS422 Converter Block Diagram.

Very High Speed Ruggedized Fiber to RS485/422 Converter Block Diagram

APPLICATION: Fiber485/422, multi-point

Model 4172 RS485/RS422 Multi-Point Application.

Isolated PC RS485/RS422 communications to fiber serial interface network.

Model 4172 RS485/RS422 interface Converter

APPLICATION: Fiber485/422 to Fiber485/422/232

Model 4172 to Model 4149/4159 Application.

Point-to-Point Isolated PC RS485/RS422 Communications.

Fiber 485/422 Model 4172 to Model 4149/4159 application; point-to-point isolated PC RS485/RS422 Communications.

APPLICATION: FiberUSB to Fiber485/422

Model 4165/4166 to Model 4172 Application.

Isolated PC USB to RS485/RS422 Communications Serial Interface Network.

FiberUSB Model 4165/4166 to Fiber485/422 Model 4172

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 4172 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 interface converters call our friendly customer support staff at 401-943-1164, email eslab@electrostandards.com, or complete our online custom product request form.

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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