Cat 5 wiring/AT&T 4 line phone FREE cabling and networking Helpdesk
 Question by Laura Elmer posted 16 Mar 2005
 Cat 5 wiring/AT&T 4 line phone
Our new office is wired in conduit with CAT 5 wiring. We wanted to use AT&T 4 line phones with a dedicated fax. The electrician has a bundle of wires sticking out of the office and no one is sure which does to what line. Additionally, the phones have jacks to connect 2 2line jacks, but we thought our wiring should carry the 4 lines. HELP! Laura
 Answer by Joseph Golan posted 17 Mar 2005
Dear Laura ,

It sounds like the electrician did not mark or terminate the cables. You are going to need someone to do this for you so connections can be made. As far as the telephones, it sounds like they are equipped with 2 RJ-14 jacks which will handle 2 lines each. Each cable has 4 pairs:
Use pairs 1 & 2 on the first jack and pairs 3 & 4 for the second.
The wiring configuration for a RJ-14 can be found at

Joseph Golan, RCDD

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