Why Conduit

Cabling-Design.com FREE cabling and networking Helpdesk
 Question by Mike Warren posted 04 Sep 2003
 Why Conduit
I work with a group that is responsible for the infrastructure of a large data/voice network.

We have been running CAT5E cable in EMT conduit (end to end) for quite some time but are questioning the cost benefit of doing so.

It seems that others I've spoken to (in the industry) don't know where there is any documented
study showing whether running CAT5E cable in EMT
has any impact (good or bad) on network performance/reliability.

Is there anyone out there who knows if such a
report exists and where I could view this report.
 Answer by Dmitri Abaimov posted 04 Sep 2003
Dear Mike,

EMT has no (positive) impact on the network performance. Unfortunately, instead, it's a big grounded conductor being put very close to the cable's wires, which increases impedance deviations along the length of the cable. That, in turn, makes Structural Return Loss parameter of the cable worse.

I think the real reason that people a usually use EMT is because plenum cables are 3 times more expensive than regular compound PVC, and you could use PVC if the cable is run inside EMT in the plenum areas. However, over time, in many instances that requirement turned into a rule of requesting contractors to put BOTH EMT and plenum cables in at the same time for just in case.

The best way to look at the EMT issue would be from NEC (fire safety) stand point. I do not know any white paper or report that would deal with performance side of the problem.

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 Cabling-Design.com 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 ...