atcomsystems.ca/forum Forums Other TDM Phone Systems Other Telephones & Systems AT&T 1070 4 co line phones

Hello and I hope all is going well. I hope I am posting this in the right forum. I have a customer that had me pull 28 voice drops for a business which is going to have 4 co lines coming in. They were going to do a PBX and then decided on the AT&T 4 co line small business phones. There is going to be 16 of these phones in office. These phones need to be wired in series and they use line 1 to communicate from one extension to the other. I wired these phones in series using three Leviton 4 co line bridge adapters that handle 9 phones on each adapter. I can access all 4 co lines at every extension with no problem. Where the problem comes in is when I dial from one extension to the next. It only works half the time and when it does the voice quality between extensions is poor and other times it is good. If im at ext 11 and dial ext 14 it may go through or it may not. I have the three Leviton 4 co line bridge adapters wired in at the demarc and my extensions come off of it and go to the different offices. My extension wiring ranges from 20ft to 60ft. I ran all my wiring using Cat5e and wired two rj12 jacks at each extension. Is this a common problem with these phones? I will take a PBX over these phones any day! Any suggestions would be greatly appreciated!

Thanks,
kkell11400

Per the manualI'd say you're over the maximum distance for wiring.

Remove some phones and see if it works, if it does there's your answer.

Also you don't say but if there is DSL on the line the filter/splitter needs to be ahead of all phones.

You are experiencing a normal problem that is usually only remedied by using a real phone system.

You generally need to use the supplied line cords because they are thicker. And as bill has pointed out total distance of wire in the setup is crucial.

Usually after about 6 phones you start having problems.

I don't think 4 line phones are ment to be used the way you are with that many extensions. Way to much cabling for good service.

its not a application for either of 4 line phone or a "PBX" a small key system is what they need . I would look at a used partner ACS it would probably price out close to the 4 line phones and have far more functionality

28 drops 16 phones to starts sounds like they plan on some growth the 4 line phones will be a constant problem and off course what happens when they need line 5 ?

Then they get 16 single line phones to put next to the 4 line phones

Unless of course they want to plan for the future in which case they can buy two lines phones instead of the single line phones

You have let the customer dictate to you what is a disaster. Wrong telephones, wrong wiring, too many telephones, etc.

The customer needs to talk to a professional telephone installation company and then decide on a key system. It can be programmed to provide simple features, and then if the customer needs anything a bit more complicated, additional features can be programmed at a later time.

The AT&T phones (They are actually not AT&T...nothing is, these days) you describe are called "consumer grade." (Are these the ones that each require 4 AA cells? Phones that require batteries to make them go are not a good idea in an office.) They are marketed to end-users, who have either a Small Office or a Home Office, (SOHO) and who are naive and gullible. You want to recommend telephones that are robust and designed for a business. "Commercial grade" in other words.

If you are new to the trade, we can help you make a logical and economically feasible proposal to the customer. We can also tell you some of the correct industry terms so that when you talk to us about your projects, we're all on the same page. We're here to help!

Here are a few of the issues that are causing you grief:

Using the Leviton products to create an MDF (main distribution frame) of that magnitude (all those cat5e wires) is asking for trouble before you even begin. Again, Leviton wiring products are accepted by many folks on this forum, but my personal policy is to remove that stuff wherever I find it and install real telephony terminals. What happens, should there be a trouble call, caused by a crimped wire, damage from some other tradesman, or a water leak? How do you intend to isolate each wiring run, during a test, without knocking out all the other non-effected phones? Answer...you can't, because the wires are all in parallel. (Not "series" as you stated). Using 66M-50 blocks, bridging clips, and cross-connections is the industry standard. This method allows quick and reliable trouble-shooting.

Cat5e wire has more copper(and therefore more impedance) per unit length than does Cat3 or Cat-nuthin. Using Cat5e in this installation was your second mistake. I hope that the customer asked for it, and you didn't recommend it. Since all 4 pairs are in use right now, there are no available spares for maintenance or expansion. I would have used Cat3 6-pair at a minimum. The problem with non-KSU (direct-wired) systems is that each line appearance requires another pair. This is why multiplexed systems have been in use for the last 40 or so years. The consumer-grade SOHO systems seem to have abandoned this concept and gone back to a time a half-century ago when every line needed a pair.

As my other colleagues have stated, 4 lines and one intercom link (that doesn't work) is not an adequate set-up for 16 people. Even if half of them are using their own cell phones or email, that still leaves 8 people fighting for 4 dial tones at any one time. Or, fighting for 0 dial tones, if all the lines are in use for incoming calls.

So, wrong phones, wrong wire and wrong terminating hardware. By the way, the two-line jacks you refer to as RJ-12 are not. They are RJ-14 if they are anything. Actually, they are 6P6C jacks wired for two-line service.

A PBX is a specific term of art. It generally has one person, the attendant, who answers the incoming calls and routes them to the appropriate extension. Extensions can call each other, generally using single-line telephones, and extensions need to dial an escape digit for an outside line. The number of trunks needs to be carefully engineered to provide adequate incoming, outgoing, and combination service. What your guys need is a key system.

Go back to the home page of this forum, and you will see a list of the major manufacturers who make very good key equipment. Try to convince your customer to buy one of those. Be sure they buy it from someone who is familiar with the product and knows how to do moves, changes and reprogramming of that particular brand.

You don't say how long you've been in our industry, but I see you registered way back in 2005, so you might already know most of what I have shared with you. Please keep us posted and we'll get you through this as best we can.

at&t consumer & small/home office phones are maufactured by V-Tech. These devices have their own "wall-warts".

I suppose they are good for home office situations where there will be only a few extensions (see ttech's reply).

Beyond that, a small key system (Avaya Partner ACS for example) with CAT 3 wiring would be the way to go.

I got called out to quote "expanding" one of these systems a few years back... the office had originally been wired for proper equipment and someone had hacked it up and slapped these in instead. After I slowly and politely walked them through the limitations they had created for themselves, they finally conceded that they needed to step up their game. Since they were a non-profit and seemed like nice folks, I tossed them a bare-bones quote for a used key system and all but offered to give my labor away. They were shocked - SHOCKED - at my nerve in suggesting they part with such a paltry sum and as I drove away, I considered myself very fortunate for not getting the work.

Run, don't walk.

Based upon the original post, it would seem that he installed one of these:
https://store.leviton.com/Bridged-Telephone-Module-bracket-47689-B/dp/B0076ZSYSW#.UgKWOKyDn2Y

That is residential media center stuff and I too would rip it out

A former customer of mine had these 4 line phones in his law office. They were all home runs of Cat 5 but at least they went to a 66 block. Swapped quite a few phones out over a year or two. Just not worth the frustration!