The U-485G USB‑RS485/422 opto‑isolated converter manual provides installation, driver setup, wiring and operation instructions.
The U-485G converts a PC's USB serial port to isolated RS485 or RS422 signals. It is powered directly from the USB port (current <50 mA) and features a DC/DC isolated power module and high‑speed optocoupler for signal isolation. The device supports plug‑and‑play operation on Windows systems and includes status LEDs for power and data transmission.
The manual covers technical specifications, driver installation, wiring diagrams for both RS485 half‑duplex and RS422 full‑duplex networks, terminal resistor settings, and recommended cabling. Installation can be done on a 35 mm DIN rail or with bolt‑hole mounting, and the unit operates from –20 °C to 70 °C. This manual is written in Chinese.
| Conversion | USB to RS485/RS422 |
|---|---|
| Power Supply | USB port, <50 mA |
| Isolation Voltage | 1000 VDC (up to 3000 VDC on request) |
| Maximum Communication Distance | 3000 m at 4800 bps, 2000 m at 9600 bps |
| Baud Rate | 300 bps ~ 1 Mbps |
| UART Data Format | 7‑8 data bits, 1‑2 stop bits, odd/even/no parity |
| Operating Temperature | -20 °C ~ 70 °C |
| Mounting | 35 mm DIN rail or bolt‑hole |
| Dimensions | 85 mm × 55 mm × 25 mm |
| Signal Terminals | D+, D‑, TXD+, TXD‑, RXD+, RXD‑, SG, FG |
Insert the converter into a USB port, Windows will detect new hardware, then run the driver installer from the supplied CD and follow the prompts.
Up to 3000 m at 4800 bps and up to 2000 m at 9600 bps.
Use shielded twisted‑pair cable with a cross‑section of at least 0.5 mm² and a characteristic impedance of 120 Ω.
The network can support a minimum of 32 nodes; the maximum depends on the RS485 input impedance of each node.