RJ31X Confusion


New Member
Hi there,

I am installing a DSC Power832 system in a new home my family is building. There is a structured wiring system in the house which splits the telephone line to all the jacks. Instead of using cat 2 telephone cable, our electrician ran everything in cat5, so that if in the future, we wished to network, we would only have to change the jack on the wall, and a few connections inside the structured wiring enclosure. As such, I honestly have no idea how i should connect the RJ31X to the Cat5, or even if it is possible to have the alarm seize the telephone with this type of setup... Any advice would be greatly appreciated!!

Thanks in advance,
An RJ31x is an interface jack for an alarm system. An RJ11 is an interface for your telephone line. Is the DCS unit an alarm system? If so, the way it wires is as follows. Wire the telephone line directly to the white/blue pair of the jack going to you alarm system, then from the white/orange pair wire to the jacks in your home that you want to have telephone service. The RJ31x interface provides an in and an out to your alarm so that if your alarm is tripped the telephone line is removed from the rest of you house (so as not to interrupt the callout to your monitoring ssrvice). It also provides a pass thru function such that if you unplug you alarm system from the RJ31x the line will route back to your telephones via a loop back connection (this is done via the alarm system when plugged in).

Can you identify the pair that comes in from the telco demarc box?

Run Cat5 between the two areas.

Take the incoming phone line, and splice it to the Blue&Blue w/White pair in the new Cat5 cable to just pulled. Connect the Orange & Orange w/White where the old incoming line was.

Structured side complete.

Go to the Alarm control.

Connect the Blue&Blue w/White to the red and green on the RJ 31x.

Connect the Orange&Orange w/White to the brown and grey.

Test for functionality...
Test phones for dial tone and incoming ring.
Test the alarm while listing to the phone off hook (dial tone), when the alarm goes off the phone should go dead.

Smile, your done. B)

I just re-read the posts, and figured out exactly the information I needed, thank you so much for your help! I really appreciate it! I'll post when im done and let you know how it worked :)
N00b question on the RJ31X: where does the jack go? From the above, it seems that it goes on the security panel side, not the telco panel.

If it's on the security panel side, what's the standard place to put it? Next to the panel, inside the panel...?

It goes in/near the alarm can. Some stick it to the back and some sick it outside, the whole point is so you can disconnect it if the alarm botches.