sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring Reasons for 568B

Canadians use eh! Americans use 568 B

Google Seach ISDN wiring standard

Their is no differance in the A or B standard they both use the same pin outs. If you where colour blind their would be no difference. If you use A on one end and B on the other you have a cross over cable... for a straight cable you need both ends the same eithe A or B...

:bow:

A makes the most sense in respects to 2 pair voice. (pin 4-5 and 3-6)

B makes the most sense in respect to T1. (pin 4-5 and 1-2)

In both of the above cases whiteblue, and whiteorange are going to be the pairs in use.

Neither a or b make sense for 10/100 Ethernet. As this type of communication uses (a) second and third or (b) third and second pair for RX and TX respectively.

RJ31X and alarm CPE make me go insane.

Regardless of chosen pin out (a or b), ring should always be on the right when working horizontally and tip should always be on the top when working vertically. Pairs should never be split when the option to maintain the pair is possible - Even for short distances.

RJ31X is easy. T/R in on 4,5; T/R out on 1,9.

Really. I don't know what the problem is except that you don't understand how they are supposed to work.

It's like Jeff says and when the plug is inserted the CO line is looped through the alarm panel then back out to the premises. If the plug is removed there are jumper bars that are part of the jack that connect the CO line directly to the premises to maintain service.

You can plug a regular line cord with a phone or butt set into the jack and get dial tone since the CO line is on the usual pins 4&5. This is one way to test.

When the alarm panel goes into alarm it disconnects the premises wiring and connects to the CO line to dial out. When that happens any call in progress will be disconnected and the line will go dead. This is another piece of information to keep in mind if troubleshooting a dead line. If you have DT at the jack but the phones are dead suspect that the dialer may be hung up. Pulling the plug out of the jack putting it in bypass will confirm.

Also, since the RJ31x is an 8 pin jack and the pre-made alarm cords are 8 conductor some alarm installers will jumper two of the unused pins on the jack and connect the corresponding wires from the line cord to a tamper zone on the panel. This will give an immediate indication to the panel that the plug has been removed and depending on how it's set up may just indicate a trouble or cause the panel to go into alarm. So keep that in mind before pulling the plug. You don't want the cops showing up.

-Hal

568A and 568B
10/100Base-T uses only the orange and green pairs
the telephone uses the blue pair
the brown pair is used for POE
:rofl:

Unless there's a difference between Canadian and American POE standards, we don't have one that provides voice anywhere. POE positive is bonded on the white/blue pair and POE negative is bonded on the white/brown pair.

LOLOLOLOLOL

Ok, then if you understand all that I said explain why you still have a problem.

-Hal

splitting pairs, and ring is on the left on the boards.

Huh? How are the pairs split.

You sound like a sparky. There are all different manufacturers of jacks and I have used many different RJ-31x's over the years. I never noticed or cared how the terminals are arranged. I just wire them as they are supposed to be wired. Most will have the diagram in the cover.

-Hal