USB to RS485 Converter in industry to support electrical isolation up to 2.5kV and
extended common mode voltage up to 25V

Product Datasheet Click Here

In most case of Windows 7/8/8.1/10 and Linux the driver will be installed automatically when the PC is connected to the Internet.
http://www.ftdichip.com/Drivers/CDM/CDM%20v2.12.28%20WHQL%20Certified.zip

Also do refer to the this manual for detailed step by step instruction.
http://www.ftdichip.com/Support/Documents/InstallGuides.htm

Specification
* Isolated RS485 Power up to 1KVrms
* Isolated RS485 Signals up to 2.5KVrms
* Extended Common mode voltage between A an B ±25V
* Works with all type of industrial equipments
– PC, PLC, SCADA, HMI, AC/DC Drives, Genset, UPS, Development Kits, etc.
* USB Power, RS485 Rx and Tx light indications for easy visibility and troubleshooting
* ESD and Surge protection for USB, RS485 and Power
* Supports all Baud Rates from 300 to 250 kBaud.
– varies on cable length
* Supports up-to 256 receivers on the bus
– also depends on the other devices connected in the RS485 network
* Very compact size 60mm x 40mm x 20mm
* ESD protection for RS485 pins
– ±16-kV Human-Body Model (HBM)
– ±8-kV IEC1000-4-2, Contact Discharge
– ±15-kV IEC1000-4-2, Air-Gap Discharge
* ESD protection for USB
– ±2-kV Human-Body Model (HBM)
– ±200-kV Machine Mode (MM)
– ±500-kV Charged device mode (CDM)
* 1 Year Warranty against any manufacturing defects