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Black Box SP390A-R3 USB to RS422/485 Converter with Opto-Isolation
- USB to RS422/485 serial converter
- Opto-isolated for enhanced protection
- Supports both RS422 and RS485 modes
- High-speed USB 2.0 interface
- Automatic data direction control (for RS485)
- LED indicators for power, transmit, and receive
- No external power supply required (USB powered)
- Durable metal casing
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Key specifications
See full specs ↓- Interface
- USB 2.0 to RS422/485
- Isolation
- Opto-isolated
- Serial Modes
- RS422, RS485 (2-wire and 4-wire)
- Data Rate
- Up to 2 Mbps
- Connectors
- USB Type-A, DB9 Male (Serial)
- Power
- USB Powered
Product details
The Black Box SP390A-R3 is a high-performance USB to RS422/485 converter featuring opto-isolation. It enables seamless communication between USB-equipped computers and serial devices operating on RS422 or RS485 interfaces. The opto-isolation provides critical protection against ground loops and electrical surges, ensuring data integrity and device longevity.
Technical Information
| Interface | USB 2.0 to RS422/485 |
| Isolation | Opto-isolated |
| Serial Modes | RS422, RS485 (2-wire and 4-wire) |
| Data Rate | Up to 2 Mbps |
Additional Specifications
| Connectors | USB Type-A, DB9 Male (Serial) |
| Power | USB Powered |
| Operating Temperature | 0°C to 55°C (32°F to 131°F) |
Description
The Black Box SP390A-R3 is a versatile and robust converter designed to bridge the gap between modern USB interfaces and legacy serial communication protocols, specifically RS422 and RS485. This device is crucial for integrating industrial equipment, scientific instruments, point-of-sale systems, and other serial devices with computers that primarily feature USB ports. The converter supports both full-duplex RS422 communication and half-duplex RS485 communication, with automatic data direction control for RS485 ensuring simplified setup and operation. A key feature of the SP390A-R3 is its integrated opto-isolation. This protection mechanism electrically isolates the serial port from the USB port and the connected device, safeguarding against damaging voltage spikes, ground loops, and electrical noise. This isolation is paramount in industrial environments where electrical interference is common, thereby enhancing the reliability and lifespan of both the converter and the connected serial equipment. The converter also includes clear LED indicators for power, transmit (TX), and receive (RX) activity, providing visual feedback on data flow. Powered directly by the USB port, the SP390A-R3 eliminates the need for an external power adapter, simplifying deployment and reducing clutter. It supports high data transfer rates up to 2 Mbps, ensuring efficient communication for demanding applications. The durable metal casing and standard DB9 serial connector further contribute to its suitability for rugged environments. Installation is typically plug-and-play, with drivers available for various operating systems, making it a convenient solution for IT professionals and system integrators.
Condition: Refurbished
Free U.S. ground shipping
Typically 1–2 days handling, 3–7 days in transit.
Purchase orders accepted
Government, enterprise, data center and small business.
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