atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring 568A vs. 568B

Originally posted by Clinton: Careful here Clinton You are from Canada and just because 568A is the standard practice here doesn't mean it is everywhere.

I believe 568A is popular here because we tend to use the BIX format wall jacks and patch panels. With the BIX jacks, wire is always terminated in order, wh/bl, bl/wh, wh/or, or/wh, wh/gr, gr/wh, wh/br, & br/wh. (Another plus for using the BIX format, don't have to look at a silly little terminating picture, just punch in order, but that's another forum topic!). When you terminate a BIX wall jack or patch panel this way and crimp a RJ45 mod connector on the other end, if you use the 568A standard, the run will be straight through. If you crimp using the 568B, you will have a x-over run.

With keystone type jacks, you specifically wire according to the 568A or B diagram and you must then terminate the opposite end the same way to be consistent.

Actually most manufacturers of hubs, switches, routers, etc. are now using the 568A standard inside their product. But again, as already stated, as long as both ends are consistent, you're good to go.

The "A" method is the standard. The "B" method is the alternate standard. TIA/EIA could not use the "B" method or 258A as it was owned by AT&T/WECO at the time and probably still is. Inclusion into the TIA/EIA standards as the alternate was simply politics.

In the mid-90s Bicsi decided(?) to use 568A because the use of two pair telephone sets. Before that the standard was 568B because of the better data flow. Now, how will I prove this?
#1 --- Pull the sheath off of 100 feet of Cat 5 and measure each pair. White blue and white green will be almost the same while the white orange will be almost a foot longer. Remember that each pair is wound around it's self as well as wrapped around the other pairs. This is for wave form matching for harmonics. Remember wires on poles? Up and down and in and out on cross arms? Merlins used 568B wiring.
#2 --- As stated above, 568B was the original WECO standard due to data transmission, even inter office between C Os. Some of you old toll guys should remember the pinouts.
#3 --- Because it works! The "A" does okay but it was mainly pushed by the Asian telephone manufacturers as an universal wiring to benefit them. It was about the same time a bunch of equipment manufacturers wanted Bicsi to go to metric sizing for equipment racks.

Bicsi sets itself up as the true guidance for the industry while it actually is run by manufacturers and CGs because they control the money.

Remember, these are standards --- NOT codes. If your specs don't call it out, do as the Romans do.

My $1--298.

KLD

And Skip 555, B will only work with two pair telephones IF you x-connect white blue and white green --- not the telephone standard white blue white orange.

I've been involved with wiring longer than I care to mention, and 568B had been the standard until the 95-96 era. One of the Bicsi RCDDs that was on the board at that time worked for Bell Atlantic Network Integration out of Harrisburg, PA. He was also the guy who inspected my contract. I got to not only see the public side of the debate but the inside debate about converting from B to A. Same for getting rid of 19/23 inch racks and going to metric sizing for every thing. Politics. The end result was what we have here now. But that's just a small bit of history. All the digital sets are one pair now so who cares?

KLD :shrug:

I should have been clearer , 568b jack to patch panel . standard line cord config plugged into patch panel and it works fine .


if you terminate to a block then yes you will need to grab white blue and white green.

I still do a fair amount of partner (two pair) and thats what we do .

single pair it dont matter

Well I guess I can use a history lesson every now and then. I always figured the "Canada 568A, US 568B" business was myth. Having never worked in the US I was giving a textbook answer. My bad.

Actually most manufacturers of hubs, switches, routers, etc. are now using the 568A standard inside their product.

Huh? Care to explain that. Ain't no such thing anymore than there is a 568A and a 568B patch cord.

All equipment ports care about is if the pinouts are correct. They couldn't care less if pins 1&2 have the W/O or the W/G on them as long as it carries through to pins 1&2 on the other end.

-Hal

Sorry, you're right Hal, I shouldn't have said "using the 568A standard." They are using the color coding of the 568A and you are right, it doesn't matter as long as the pin outs are correct.

Even most premade patch cords are using the color coding of 568A now, again it doesn't matter as long as it is carried straight through.

And while on this topic;
How many have seen IT guys make their own patch cords and just crimp the wires in pairs from 1 to 8?

The copper doesn't care what color coating it has, it just wants to be on the right pin.
Mark