... ty of computer serial prot or q ' ty of 485hub port, support 256pcs portsOperation Temperature- 40 C~70 COperation Humidity10- ... Distance less than 13m, suggestion distance is 3m or less RS485: bus line max length 1200m, suggestion length 1000m or ... net coverage areaCollocationsPCB board, case, power, power line, serial port communication line, software, manual, certificate, key(2pcs), cartonAlarm for ...