Search CE Pro

Print  |  Email  |  Share  |  News  |  Follow on Twitter, Facebook, Google+ or RSS

Category Cabling: TIA-568a or TIA-568b?

Dealers on Remote Central debate Cat 5/6 wiring standards. Should you use TIA-568a or TIA-568b for residential installations?

Should you use TIA-568a or TIA-568b standards for Cat 5/6 residential installations? If you’re wondering the same thing, check out the dynamic discussion in the Custom Installers’ Lounge at Remote Central.

Dealers are debating which wiring scheme makes sense, and if it even matters. The responses are mixed, but pretty much even between A and B. Naturally, all dealers agree that on retrofits, make sure to check how the existing Cat 5/6 wires are terminated.

Here are some of the comments. Click here to read the entire discussion.

(Comments edited for grammar and clarity.)
We have always used 568a but have recently converted to 568b mostly because of the baluns that require that standard. Bottom line is it really doesn't matter which one you go with as long as you choose one.
With POTS [plain old telephone service] becoming a thing of the past in residential and 568b being a lot more common, I'd say going with B perhaps is a better choice.
I use B all the time, but recently installed some phone lines in a doctor's office where he uses a Panasonic non-KSU system using all four pairs, and after the third jack I realized I was using A.

Murphy's Law actually came to the rescue this time, because when I went to punch down on the phone module, it turned out that the RJ-45 jacks are wired for A. Imagine that!

Then there's the IT guy I spoke with recently who was a bit puzzled when I told him I use B. He was dissatisfied with that answer until I told him that when there's an existing system, I look to see what they used, and use that.
My cousin runs the IT dept. at a hospital .... He uses B and said A is for phone guys!

As long as you’re consistent, either should work just fine.
If the house has an even number it's A; if it's an odd number then we go with B.
We do A at every job. Patch panel and wall plate are always A. Breakout cables/patch cables can be whatever we/you want.
I always use A. Only a handful of times have I seen B used and that was commercial.
I switched to B several years ago as A is really an old standard that was for the phone guys. B is used in all proper IT installations and if you've ever checked the pre-built patch cords you will notice that they are wired as per the B standard. Therefore, why make life difficult for yourself?
I got tired of the debate and created my own pattern: brown, blue/white, green/white, blue, orange/white, green, orange, brown/white.
Me too, 568C.
I guess all the people posting using B in a residential job never use the structured wiring cans. OnQ, Open House, Leviton, etc... ALL!!! use A. I have never seen it otherwise.

I agree it's a pain in the butt to always have to look if the system you're using is wired A or B. But until these manufactures get their crap together and pick one wiring scheme, we are going to have this confusion.
I use pro RJ-45 patch panels in larger homes and they are usually “helpfully” (confusingly) identified with both standards. It's always bugged me that the shade of colors used on the punch down blocks on the patch panels and often on the keystones is sometimes so poor that orange can look like brown and green like blue. Yeah, I know, get a better flashlight ….
Actually, I would think that using A or B could make a huge difference in some products depending on the twisted pair that is twisted the most.

We have switched to B but always check to see what each product requests. I know that I tried to use a balun with A once and could not get it to work. The product did not mention anywhere that I needed to use B but once I made it B, it worked.

Just for kicks I tried again and tested everything. Didn't work. As far as OnQ, I am pretty sure we used B on the last few jobs we did and had no issue. Sometimes it just does not matter. Sometimes it does.

Behind every successful custom installation is a CE Pro

And CEPro magazine is there keeping you up-to-date on the latest products, techniques, designs and business practices. From HDBaseT 2.0 to cat5e wiring, from UHDTV to wireless lighting control, CEPro explains how they work and how best to use them. Each issue delivers constructive, real-time content to help you find innovative ways to successfully build and maintain your business.
Discover how to make smart use of today's current technologies...and those that are emerging...subscribe today!

Subscribe to the CE Pro Newsletter

Article Topics

News · Product News · Wire and Cable · Structured Wiring · Datacomm · All topics

About the Author

Julie Jacobson, Co-Founder, EH Publishing / Editor-at-large, CE Pro
Julie Jacobson, recipient of the 2014 CEA TechHome Leadership Award, is co-founder of EH Publishing, producer of CE Pro, Electronic House, Commercial Integrator, Security Sales and other leading technology publications. She currently spends most of her time writing for CE Pro in the areas of home automation, security, networked A/V and the business of home systems integration. Julie majored in Economics at the University of Michigan, spent a year abroad at Cambridge University, earned an MBA from the University of Texas at Austin, and has never taken a journalism class in her life. She's a washed-up Ultimate Frisbee player currently residing in Carlsbad, Calif. Follow her on Twitter @juliejacobson. [More by Julie Jacobson]

3 Comments (displayed in order by date/time)

Posted by brian  on  06/23  at  01:23 PM

I believe this decision was made by the EIA/TIA Board under the EIA-TIA570A and B Residential Standard which refers to the connections for residential being the 568A standard (please correct me if I am wrong).  Commercial is almost universally 568B as it too is defined in their standards.  As I don’t install hardly any commercial, I have never gone searching for the governing documents.

On the Balun point I have seen that in some manufacturers documentation, so generally I will terminate to their prefered standard.  However I have never seen a difference.  With Baluns the use of patch cords is not a good idea so they are usually direct point to point connections (ie no patch panels) so stepping outside of the Residential standard is much like any other custom connection.

Another concern is EZRJ45.  I have found in just one random document (wish I could remember where) from a manufacturer to not use them.  We use them all the time, never had an issue.  Anyone else ever have a problem?

Posted by Frank Di Bartolo  on  06/24  at  01:45 AM

Hey guys, when it comes to wiring for products like ABUS, the only difference in 568A and 568B wiring is swapping left and right Audio channels.

As for baluns, we wire whatever standard the supplier recommends.

Others have commented to test 1st and then be consistent, I like that idea too!

Posted by Kumar Ranjit  on  06/25  at  01:53 AM


So for a new Home environment installation what do you guys suggest go with a or b ?


Page 1 of 1 comment pages
Post a comment
Commenting is not available in this weblog entry.

Sponsored Links

  About Us Customer Service Privacy Policy Contact Us Advertise With Us Dealer Services Subscribe Reprints ©2015 CE Pro
  EH Network: Electronic House CE Ideas Store Commercial Integrator ChannelPro ProSoundWeb Church Production Worship Facilities Electronic House Expo Worship Facilities Expo