We have an office with several telephone lines working under the same number.

We are using super old phones (4-line phone devices) in each line. 2 of them did not work and we bought 2 new Panasonic 4-line phones.

Our old phones have only 1 phone connection that goes to the wall's phone connection. The new phones come with 4 different connections (1/2, 2, 3/4, 4 being these numbers the lines).

Now, when I connect the new device from the 1/2 connection to the wall's line connection, the phone is working as an independent line and none of the other lines (2,3,4) work at all. Also, I can call out but I cannot pick up if there are calls coming in.

How should I connect my new 4-line phones so they integrate with the current internal network?



closed as off-topic by Ecnerwal, Bryce, Tester101 Feb 9 '15 at 13:01

  • This question does not appear to be about home improvement within the scope defined in the help center.
If this question can be reworded to fit the rules in the help center, please edit the question.

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    I'm voting to close this question as off-topic because It does not appear to be about home improvement - it's about a business telephone system not likely to be seen in a home (even in a home business.) – Ecnerwal Feb 6 '15 at 1:06

It would help to know what your old phone make and models were and what the models of the new phones you got are.

Based on what you provided so far I have a feeling your old system was a keyed system with a KSU or possibly a pbx and your new phones work without a KSU. The new phones are not compatible with your current phone system.

In a keyed system with KSU (this is also similar if you have a PBX as far as wiring goes) you're going to have some sort of box (KSU or PBX) mounted in a rack or more commonly on the wall for small systems. All the incoming lines will connect to this box.

All the phone lines that go to your phones will also be connected to your KSU. The phones usually only need one pair of wires going to them from the KSU to be able to access all incoming lines. The connection between a phone and a line is done through the KSU. The phones are digital phones that need to be compatible with the KSU you are using. Think of it sort of like a network switch or router for your phone system.

In a keyed system that doesn't use a KSU (like a lot of the panasonic phones that have individual line ports) all 4 incoming lines go to each phone. The signals going to your phones are just the regular analog phone lines. So each phone is basically directly connected to each incoming line. These are not digital phones and won't work with a KSU.

One thing to note, I simplified the connections but most likely you'll have a number of 66 blocks where the wires are actually terminated and not going directly into the KSU.

Update after phone models added:

Unfortunately I guessed correctly. The new phones won't work with your existing setup. You can either:

  1. Get phones intended to work with you system (check model number of the KSU first). Even though Nortel went out of business you can still find used/refurbished phones for those systems. This is the easiest and cheapest option but you're stuck with an old system that is no longer made. All you have to do though is plug in the replacement phones.
  2. Get a whole new system with new KSU or PBX and compatible phones. Get a similar system that can support your incoming lines and send one pair of wires to each phone. This should be pretty straight forward but you might need to hire someone to set it up. If there's any rewiring needed it should only be some minimal changes at the telecom closet. I haven't used it but the XBlue X16 system seems very popular and should work with your setup with maybe some minor rewiring of cross connects at the 66 block.
  3. Get rid of your old system and use the new phones on their own. This is going to require that you have 4 pair wire going from the telecom closet to each phone jack. If you already do have 4 pair (8 wires in the cable) going to each jack then with some minor changes you can use the new phones. If you don't have 4 pair cable going to each jack you're going to have to run new wires which can be expensive.
  • Also important: with a key system (or a PBX) you can only use phones that are designed to work with that system. Mixing in regular analog phones (including a multi-line phone that connects directly to PSTN lines) will not work: if connected as an extension, it will probably just malfunction (or worse, damage your PBX); if put in parallel with the KSU/PBX you'll have usability issues including not being able to transfer calls properly, collisions when you pick up lines in-use, and voice mail won't work properly (if your KSU/PBX has that). – gregmac Feb 5 '15 at 19:03
  • phone models in updated question. thx – samyb8 Feb 5 '15 at 19:23
  • @samyb8 updated my answer to provide you options on what you can do now. – OrganicLawnDIY Feb 5 '15 at 19:47

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