UOTEK
UOTEK UT-861A USB to 4-Port RS-485 RS-422 Data Converter
A USB 2.0 converter adds four optically isolated RS-485/RS-422 DB9 ports with automatic baud-rate detection up to 128000 bps and 2500 Vrms isolation per circuit
- TypeConverter
- Connector AUSB-B
- Connector BDB9 Male
- Supports 128 devices per converter for large multi-drop networks
- 2500 Vrms isolation protects equipment from ground loops
- Surge and ±15 kV ESD protection on every serial channel
- Automatic baud-rate detection from 300 to 128000 bps
- Operates from -40 °C to 85 °C in harsh environments
Industrial RS-485/422 Hub
This new UOTEK UT-861A converter connects a USB 2.0 host to four isolated DB9 serial ports. Each channel handles RS-485 or RS-422 signalling in half-duplex or full-duplex mode at up to 128000 bps. Optical isolation rated at 2500 Vrms protects the host from ground loops and transients.
Integration Engineers and Field Technicians
Suits engineers adding legacy serial instruments to modern PCs without opening the chassis. The 128-device multi-drop capacity fits large sensor networks. Not for installers who need DIN-rail mounting or screw-terminal wiring instead of DB9 connectors.
Four Independent Isolated Channels
The decisive spec is four galvanically isolated DB9 ports sharing one USB-B upstream link. If the application requires only a single serial link or cannot use DB9 connectors, a single-port adapter or terminal-block model is the correct choice.
Highlights
- Supports 128 devices per converter for large multi-drop networks
- 2500 Vrms isolation protects equipment from ground loops
- Surge and ±15 kV ESD protection on every serial channel
- Automatic baud-rate detection from 300 to 128000 bps
- Operates from -40 °C to 85 °C in harsh environments
Specifications
| Brand | UOTEK |
|---|---|
| Model | UT-861A |
| Type | Converter |
| Connector A | USB-B |
| Connector B | DB9 Male |
Questions about this item
Should I pick the 2-wire half-duplex or 4-wire full-duplex mode for my RS-485 RS-422 network?
The converter supports both modes simultaneously; choose 2-wire for simple multi-point buses or 4-wire when you need full-duplex throughput on the same DB9 port.
What does the 128000 bps headline baud rate deliver over a 5000 m cable run?
At 128000 bps the rated distance drops to 300 m; to reach the full 5000 m you must run at 9600 bps or lower.
How does the USB 2.0 interface limit the four DB9 ports in practice?
The USB 2.0 link caps aggregate throughput at 128000 bps shared across all four ports, while each DB9 channel remains optically isolated at 2500 Vrms.
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