... Industry-specific, antistatic, anti-jamming, 600 W lightning protection . USB TO three wire RS485 converterIndustry-specific, antistatic, anti-jamming, ... supply: there is no external power supply, power supply by USB ports.2), system requirements: Windows/ME / 2000 / XP/ ... medium: twisted pair or shielding wire;11), Transmission distance: USB to turn 485 transmission distance: 1.2 km above;12 ...