sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services T1's, CSU's and DSU's Question about T-1 and Fax equipment

Looking for some advice/documentation on T-1 and Fax equipment.

I am in the Copier / Fax / Printer business and I frequently run into problems with Fax equipment having transmission failures when the customer is getting their phone connection exclusively via T-1 (or other data solution). In our own building we have our phones coming in via T-1 but we have a few "analog fax lines" to help prevent problems. Most of the fax manufacturers reccommend this setup and if we call tech support for any fax communication problems as soon as they here T-1 they say that is not supported but they can't explain why.

can anyone give me a technical reason or point me to some documentation why fax equipment and T-1 can't get along?

Most of the times I see trouble with faxs on a T1 it is due to timing errors and slips on the T1 itself. Report the issue to your carrier and req they test your t1

I agree with Anthony, If this T-1 is having slips then any dial-up PC's are most likly getting dumped as well.

Thanks for your help!

Are you on a ATM or TDM product.
Most fax issue come with the ATM product because the compression on the line in the core router is not set properly.
Lines for phone systems do not need the same compression so they never think to change the one fax line/alarm line.