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

Not sure what you are referring to there. As Hal said, and as I have always done, just wire it up as the jack or equipment specifies. Usually diagramed out for you. Never have had a problem.

Pin 1 and 6 is only a valid pair in RJ61. And to my knowledge no one uses RJ61.

Thus its either the pin out on the line cord is:
A) Not a Standard
B) Splitting pairs

Either or is fine with me.
Regardless, the inconsistencies from general telco practices require extra care when modifying the installation. This "make me go insane" as most alarms are either wired in poorly with no jack or -more commonly- as a set.

Here we run our ADSL/VDSL2 line though the alarm system before it goes into a potsplitter. This means the integrity of the alarm installation is very important to ensure a quality installations.

And, Almost every job I work on requires disconnecting the alarm from OE at one point in time. Either for tests, verification, or adding highspeed equipment. I am aware of two times when Police arrived at a job site for a number I was working on - and it was because of an OSW trouble (s/c) on a fax line that rang though to 911. However the Idea of a temper switch being wired into the line seems smart, I know of one job where a fake nid was installed with a tamper line running though it. The idea was If the line was cut it would be very obvious that someone was trying to disable the alarm as the OSW didn't actually go anywhere but inside.

You dont have any issues running your ADSL/VDSL thru an alarm panel and putting the filter/splitter behind it? I always try to avoid putting any form of DSL on alarm lines...and if I do, try to put the filter ahead of the panel. If I try to go behind the panel, I have seen some of their equipment affect train rates on the modems.

Company policy to install the potsplitter AFTER any alarm/CPE designed to seize the line.

If the ptsp is before the alarm system then any s/c in the ptsp/modem/bonds or on/in the isw/jack could cause the alarm to not properly function in an emergency situation.

I'm not sure that I understand you on this. An RJ61 is a four-line jack, with line 1 being on pins 4/5, line 2 on pins 3/6, line 3 on pins 2/7 and line 4 on pins 1/8.

I think he is talking about the pinout on USOC jacks. With an RJ61 jack, pin 1 is tip and pin 8 is ring? (dunno, I didn't look) and he considers only those pins to be a "valid pair" because tip is on the left somewhere?

Could it be that he thinks the pairs are split because the only T&R that is on adjacent pins is 4&5?

-Hal

Well, if the alarm dialer doesn't hang anything on the line while it is inactive- IE there is just a DPDT relay that transfers the line, then there should be no problem with DSL. Thing is that most monitor the line for ringing and loss of battery so that is going to disrupt DSL the same as a phone without a filter.

I don't know if this has been changed with security panel manufacturers now including a DSL filter in the panel but I wouldn't want to take the chance and use a DSL line for security.

-Hal

woops, sorry I Meant pin 1 and 8 not 1 and 6.

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

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Jeff Moss

I think that is correct for alarm jacks

I have always used 568A. I see some people using 568B. it does not make any difference technically.

568A & 568B pins 4/5
the blue pair is used for telephone:
brown pair pin 7/8 is not used.
except POE uses brown pair 568A & 568B

10/100Base-T systems

I am going out to beat my dead horse...