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Black Box Network Services SP390A-R3 USB to RS422 & 485 Converter with Opto-Isolation
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Overview
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MAIN OVERVIEW FEATURES: Total Number of
Ports:
2USB: YesPower
Source: USB
Height:
3"Width: 1.7"D
epth: 0.8"E nvironmentally
Friendly: YesEnvironmental
Certification: RoHSWEEE
Country of Origin: United
StatesTAA Compliant: YesLimited
Warranty: 5 Year
Ports:
2USB: YesPower
Source: USB
Height:
3"Width: 1.7"D
epth: 0.8"E nvironmentally
Friendly: YesEnvironmental
Certification: RoHSWEEE
Country of Origin: United
StatesTAA Compliant: YesLimited
Warranty: 5 Year
Warranty & Returns
Warranty, Returns, And Additional Information
Return Policies
- Return for refund until: January 31, 2027
- Return for replacement until: January 31, 2027
- This item is covered by Newegg.com's Extended Holiday Return Policy.
- Read full return policy for details.
We want to ensure your holiday shopping this year is hassle-free. That’s why we’re automatically extending our return policies on almost every product! For purchases placed between November 1st, 2026 and December 31, 2026 you will have until January 31, 2027 to return your product.
Manufacturer Contact Info
- Manufacturer Website
- Support Phone: 1-877-877-2269
- Support Website
- View other products from Black Box Corporation
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The Black Box SP390A-R3 is a USB-to-RS-422/485 converter with opto-isolation, suited to technicians and system integrators connecting a USB-equipped computer to serial equipment in applications that need RS-422/485 range or multidrop communication and protection from ground loops or voltage spikes.
Recommended For
- Industrial automation technicians connecting a USB-equipped PC to RS-485 PLCs, drives, or other controls—especially when the link needs 2-wire multidrop or 4-wire RS-422/485 operation.
- Instrumentation and lab staff adding an isolated RS-422/485 connection to a USB-only computer, where electrical isolation from ground loops or voltage spikes matters.
- Field-service engineers who bring a laptop to legacy RS-422/485 equipment and need a USB-powered adapter that appears as a COM port for existing Windows applications.
- Users linking a PC to a long-run or multidrop RS-422/485 installation who need a terminal-block connection and transmit/receive status LEDs for basic connection checks.
Spec Summary
| Attribute | Value |
|---|---|
| Best For | Connecting a USB host to RS-422/RS-485 serial equipment |
| Brand | Black Box |