DIY Home Improvement, Remodeling & Repair Forum > DIY Home Improvement > Electrical and Wiring > Preventing noise in Ethernet cables




Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old 01-10-2013, 03:03 PM  
drewdin
Junior Member
 
Join Date: Aug 2012
Posts: 391
Liked 25 Times on 22 Posts
Likes Given: 78

Default Preventing noise in Ethernet cables

Hi All,

In multiple places the electrician ran the ethernet cable along side the power cables in the room, I want to try and prevent as much noise as I can, I have read that all I need to do is cover the areas with tinfoil to prevent noise.

My question is, is it that easy? Will tinfoil work or is there something else I can do that will work better? Removing the cables and re-routing them is out of the question.

Any recommendations will be greatly appreciated, Thanks!



__________________
drewdin is offline  
 
Reply With Quote Quick reply to this message
Old 01-10-2013, 06:05 PM  
JoeD
Contractor
 
Join Date: Mar 2006
Location: Welland, Ontario
Posts: 946
Liked 99 Times on 81 Posts
Likes Given: 2

Default

Around the Ethernet cable shouldn't hurt but do not wrap the electric cables with tin foil.



__________________
JoeD is offline  
 
Reply With Quote Quick reply to this message
Old 01-10-2013, 06:43 PM  
drewdin
Junior Member
 
Join Date: Aug 2012
Posts: 391
Liked 25 Times on 22 Posts
Likes Given: 78

Default

I only planned on covering the ethernet cables, just to verify. Is that the best way to prevent noise? Is there anything better that you would recommend? Thanks

__________________
drewdin is offline  
 
Reply With Quote Quick reply to this message
Old 01-10-2013, 07:24 PM  
nealtw
Contractor
 
Join Date: Nov 2010
Location: vancouver, b.c.
Posts: 9,660
Liked 784 Times on 699 Posts
Likes Given: 1346

Default

If that work's, would that aluminum tape they use for sealing ducts work, it is sticky allready. No not duct tape!!

__________________
nealtw is online now  
 
Reply With Quote Quick reply to this message
Old 01-10-2013, 07:43 PM  
Wuzzat?
Banned
 
Join Date: Jan 2010
Posts: 2,328
Liked 167 Times on 154 Posts
Likes Given: 94

Default

I searched on

"bit error rate" romex ethernet

but didn't come up with a document that related the three in a way useful for you.

I'd recommend cutting wood on a table saw powered by an extension cord or a length of Romex that your Ethernet cable is wrapped around for a few feet. If your data transfer rate doesn't slow noticeably because the parity bits don't match then I'd say you're OK with the installation.

Supposedly there is also smart home cabling that runs both power lines and data lines together.

Non-ferrous metal (foil) will not shield against the primarily magnetic field (H field) radiated by power cables. Foil or braid attenuates or reflects electric fields (E field), like nearby radio station transmissions.

__________________

Last edited by Wuzzat?; 01-10-2013 at 07:50 PM.
Wuzzat? is offline  
 
Reply With Quote Quick reply to this message
Old 01-14-2013, 12:25 PM  
CallMeVilla
Contractor
 
CallMeVilla's Avatar
 
Join Date: Feb 2010
Location: San Diego
Posts: 1,243
Liked 377 Times on 295 Posts
Likes Given: 151

Default

Shielded Cat6 cable is the minimum quality you should use. It is designed to protect itself from outside interference, BUT, it is recommended to NEVER run them side-by-side to your electrical wiring (Romex). Typical is to run electrical down one stud and the Cat6 down a different stud.

If you ever have to cross the Romex, make sure you do it at right angles (perpendicular) so you minimize the chance of interference. I ran 4,000 ft of CAT6 in a smart house and used this approach throughout. No interference issues developed!

Good luck!

__________________
CallMeVilla is offline  
 
Reply With Quote Quick reply to this message
Old 01-14-2013, 12:48 PM  
drewdin
Junior Member
 
Join Date: Aug 2012
Posts: 391
Liked 25 Times on 22 Posts
Likes Given: 78

Default

@vanilla, the cat5e cable has already been run. I cant change its location now, all i can do is try to prevent any noise. Any suggestions?

__________________
drewdin is offline  
 
Reply With Quote Quick reply to this message
Old 01-14-2013, 12:54 PM  
Wuzzat?
Banned
 
Join Date: Jan 2010
Posts: 2,328
Liked 167 Times on 154 Posts
Likes Given: 94

Default

Quote:
Originally Posted by CallMeVilla View Post
BUT, it is recommended to NEVER run them side-by-side to your electrical wiring (Romex). Typical is to run electrical down one stud and the Cat6 down a different stud.

ran 4,000 ft of CAT6 in a smart house and used this approach throughout. No interference issues developed!
Can you post links for this, preferably by the IEEE (no Mike Holt)?
The science may say it would make no difference, running parallel or not, but I don't know for sure what may happen in the real world.

In the 4000' case there may not have been interference in any case (the ad hoc fallacy) but this issue comes up frequently enough on forums for me to want some science links to verify.
You may after all be right, and this particular issue has never came up in my work so I haven't dug into it.

My main misgiving has to do with the qualitative separation of 60 Hz sine wave magnetic fields vs. the high frequency square wave electric field (which is totally contained within the shield) used in data transfer.

If there is interference, drewdin, you may be able to get a "60 Hz notch filter" to reduce it.
__________________

Last edited by Wuzzat?; 01-14-2013 at 01:04 PM.
Wuzzat? is offline  
 
Reply With Quote Quick reply to this message
Old 01-14-2013, 01:06 PM  
CallMeVilla
Contractor
 
CallMeVilla's Avatar
 
Join Date: Feb 2010
Location: San Diego
Posts: 1,243
Liked 377 Times on 295 Posts
Likes Given: 151

Default

Happy to share ... Here are some links that all poride bits and pieces of useful information:

ROMEX and CAT6: http://www.tek-tips.com/viewthread.cfm?qid=1416430
HDMI and other issues: http://www.remotecentral.com/cgi-bin/mboard/rc-custom/thread.cgi?16953
Install issues: http://www.electrical-contractor.net/forums/ubbthreads.php/topics/198957/all/Cat6_installation.html

__________________
CallMeVilla is offline  
2
People Like This 
Reply With Quote Quick reply to this message
Old 01-14-2013, 04:14 PM  
Wuzzat?
Banned
 
Join Date: Jan 2010
Posts: 2,328
Liked 167 Times on 154 Posts
Likes Given: 94

Default

The plot thickens: look at claim 1 of
http://www.freepatentsonline.com/6998538.html

"We claim:

1. A hybrid electrical cable providing for power transmission or distribution and low power signal communications, the hybrid cable comprising: a) a power cable including a first group of one or more conductors for conducting power; b) a power cable insulation jacket overlying the first group of one or more power conductors, the power cable insulation jacket including a first layer comprising a soft magnetic material having a coercivity of 1 oersted or less; c) a group of one or more low power signal conductors disposed exterior of the power cable insulation jacket; and d) an outer jacket overlying the power cable, the power cable insulation jacket and the group of one or more low power signal conductors, the outer jacket comprising a metallic material."

Apparently Ulectra Corporation (North Miami Beach, FL, US), the assignee, is producing this thing.

So here's your ferrous metal for mag field shielding (use BX cable!) and the patent does mention shielding later on as a design constraint and so drewdin may have to resort to extraordinary measures to keep his Ethernet functioning to full capacity.

Or, he may luck out.

And this
"by absorbing radio frequency (RF) electromagnetic emissions generated by high voltage, high frequency electrical transients which may be present on one or more power conductors of the power cables due to external high frequency electrical disturbances."

implies that the problem is not so much the 60 Hz but that the Romex acts as an antenna to pick up, or conduct, all kinds of electrical noise.
In this case the Ethernet may work better late at night when the PoCo customers are asleep.

BTW, when I left the USPTO the patents were just beginning with the 5,100,000 numbers. IIRC, they had 20% turnover each year. . .and I lasted a few years.



__________________

Last edited by Wuzzat?; 01-14-2013 at 04:36 PM.
Wuzzat? is offline  
drewdin Likes This 
Reply With Quote Quick reply to this message
Reply


Quick Reply
Message:
Options

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter DIY Home Repair Forum Replies Last Post
Noise after window job jkb3792 Windows and Doors 11 04-02-2014 04:43 PM
Too much noise upstairs, help! spaghetti0625 Insulation and Radiant Barriers 1 03-14-2011 05:23 PM
Solution for Unsightly Cables Cristina88 Decorating and Design 3 11-03-2010 09:54 AM
Pipe Noise steve12 Plumbing Forum 3 06-20-2008 09:03 AM