RS232 and RS2485 FREE cabling and networking Helpdesk
 Question by tammy s. dulin posted 25 Jul 2002
 RS232 and RS2485
I was wondering what the run link of cable that can be used for RS232 and RS485 communications.
 Answer by Dmitri Abaimov posted 01 Aug 2002
Dear Tammy,

RS 485 devices can be connected directly to the twisted pair conductors (CAT3 or better) because this protocol uses balanced signal.

RS 232 is unbalanced-signal protocol therefore you are required to either use 'balun' (balanced-to-unbalanced) adapters or limit your distances to ~ 90 meters (270 ft) at 9.6Kbod speed. With (active) balun devices you can go more than 12 km (40,000 ft).

These balun devices are widely available from any decent cable distributor/reseller.

Dmitri Abaimov, RCDD

Click here to see the expert's profile
Back to the current page of questions | Back to all the questions
Back to HELPDESK | Ask your question
Residential Cabling Guide

Home Cabling Guide

Finally, an instantly downloadable book that saves you thousands in home improvement dollars! Enjoy living in 21st century technology-advanced home while increasing its selling value and competitive advantage on the real estate market. Whether your cabling is for home office or high-tech leisure, you can wire your home yourself or learn "wirish" to speak with your cabling contractors in their language!

Learn more ...