atcomsystems.ca/forum Forums TDM Business Telephone Systems Avaya - Lucent Telephones & Systems loud buzz in Partner 18d phone

I am having a bear of a time trying to troubleshoot a buzz on my Partner 18d phone. I just installed an ACS 7.0 proccessor and have 4 phones installed on the system. The wiring is cat5e cable and was installed throughout the house during a recent rehab. Two of the phones have no problems. The third phone has a slight but annoying buzz. The fouth phone has the worst buzz, Very Annoying. I have done various swaps with each phone to see if it is a phone problem. Every phone I put on phone line #4 has the buzz on it. I take the phone down to the basement to the ACS and plug it directly into the unit and the sound is clean, no buzz. So, obviously it's in the wiring. I "assumed" that cat5 cabling would be a good choice for any emf issues, I guess I am an "ass". Anyway, after many hours of frustrating troubleshooting I am at a loss on how to get rid of this buzz. Before you ask, it is difficult to run any new lines to this part of the house without breaking walls. I already have a second cat5 cable in the same wallbox but that does the same buzzing. I was wondering if the was some kind of a choke that would work.
Any thoughts would be appreciated. Dave

Sounds like EMF to me, especially since you said you've used a different cable same results. Assuming there is no physical cross between the talk path and the data pair, kill the power at the breaker panel except for the phone equipment and turn them on one at a time until you find the one causing the problem. Then you'll have to work on those outlets/lights to see which ones causing it. Normal house wiring shouldn't cause this and I'm assuming you know the phone is not close to anything that would cause it. There are chokes, but this problem should be fixed if possible instead of covered up. One thing on EMF the longer the wire the more the noise, so the source could be anywhere. So make sure you don't have anything close to the KSU that could be causing this also. You may try grounding the unused pairs also, but this probably won't fix it.

Before you condemn the wire have you got the pairs correct and the jack wired correctly? How have you got the "CAT5" connected to the port on the ACS?

Now I'm a little confused by- Every phone I put on phone line #4 has the buzz on it.

Are you saying that if you pick up CO line 4 on phones at these two locations you hear a buzz but you don't hear it on lines 1, 2 and 3? Also, when you plug a phone directly into those same extension ports on the ACS there is no problem?

-Hal

I assumed he ment the 4th station port. I also assumed correct wiring with no crosses. I know what assuming does and it won't be a first.

Make sure it is 568B --- and justbill is correct about the grounding of unused pairs. This is "ass-u-me"ing it is on a block and cross connected -- not with a plug crimped on the end.

If both cables are "humming" the power issue that justbill suggested will assist you in finding the problem but if the wiring is not properly installed it will not help you much. Not run in the same holes drilled for electrical, run over lights with ballasts, or pinched / in tight turns.

Good luck,

KLD

Exactly. Usually problems like this are not caused by the wire itself unless possibly it was skinned or nicked and grounded somewhere.

I had a problem like this once that was caused by a cat urinating on the jack.

I would be almost positive that this is not an EMI problem but rather something you did.

-Hal

I'm guessing that it's not wired 568-B or even USOC 2-pair, and you're hearing the "data" on the 2nd pair bleeding into the voice pair.

Y'all are probably right about bleed from the data pair. I'd think if it were EMF he'd describe it as a hum more than a buzz. Guess I'd have to hear it to know. One thing if he kills the AC he'll know for sure, especially if he has a UPS on it to isolate all power. I've only had one where the data pair was interfering it was obvious and I could see a cross between the pairs.

Right. The cat urine left a residue in the jack that bridged the data pair and the T/R pair with enough resistance that the data bled over to the T/R.

-Hal

Hey guys thanks for the replies, I didn't explain my system enough to you before so I will correct that now. I am a facilities manager and am pretty competent with the Partner Phone Systems. The house that I installed this new Partner ACS 7.0 houses 4 priest with seperate private lines to each suite/bedroom and also one phone in the kitchen. They all have their own private number and line. Line 4 is the one that is giving me fits. I have taken the phone from the problem wall jack(#4) and plugged it in directly to the ACS downstairs. There is no buzz on line four at that point. Line 4 is used strictly as a point of reference. I have swapped
all the phone company lines with this cable going to the problem wall jack and the problem does not change the buzz/hum stays no matter what phone line I put on the cable.

I did some more troubleshooting today and ran a new cable, Cat5, thru the house directly from the ACS to the phone jack. The buzz was not there. Which of course tells me there is a problem with both cat5 cables in the wall. I stated in my first log that it is difficult to run a new line through the walls with out major wall holes. The house was rehabbed in the last year and is looking pristine. Is there any thoughts on using the existing wires. Thanks again for the responses. Dave

What happens when you put an SLT on it or butt set instead of the digital set?

I missed justbill's reply before sending my last response. I will definitely try the circuit breaker suggestion hopefully that will at least narrow things down. Thanks guys. Dave

Since you cant easily run a new cable

why dont you swap the pairs on your existing cables and see if you can get 4 good wires out of each

If you have a cat5 cable tester test the cable
make sure theres no power on it from ACS
maybe you can find the 4 wires you need

I do have a butt set and the hum is still there.
One other thing, before I installed the ACS I originally install a multi-phone stand alone system and that did not have this buzz problem. I have put back this phone and I do not her the buzz. If it is there it is very muted.

KENB, I have tried all 16 wires in various configuration, same problem. When you say test cables make sure there's no power on it from the ACS. I'm a little confused because all
four(both pairs)cables have 48 volts on them. isn't this normal.

OK so now if I'm hearing you right the buzz is only there if the CO line is going through the partner system. Is that correct? If you run the CO line to the same jack but not through the partner there is no noise?

justbill, no I connected the wires to my punch block which is connected to the ACS.

Yes, you are going to see voltage on the T/R pair (w/bl) and the power/data pair (w/or). Don't remember if it's 48 volts but it's about right.

I would like to see you check with a cable tester, something like the Siemens that will check for shorts, opens and crosses. Not going to find a ground though.

I asked you before exactly how you have the 4pr cable connected to the ACS port. Did you just press on a 6 position plug on two pairs? I'm going to assume you did and would hope that the two center pins, 3&4 have the w/bl pair on them and pins 2&5 have the w/or pair on them.

You said you checked with a butt set. If my assumption above is correct then you are saying that you connected your butt set to the w/bl pair and heard the hum with a dial tone?

What I want you to do now is cut or disconnect the w/or pair on the plug back at the ACS port and listen on the w/bl at the other end with your butt set as you did before. What happens?

Oh, I should point out, DON'T cut the w/or with the plug connected to the port. When this pair is shorted power on it is interrupted and you will have to reset the system (turn it off then back on) to reset the port. This will have no effect on your butt set or a single line phone but a system phone will not operate.

-Hal

Hal, I'm not on site at this time, but I have been working on this problem for hours and hours and I believe I tried your suggestions. I did notice early on in my troubleshooting that as soon as I connected the power wires(orange) without any phone co wires(blue), the hum was already there. I Picked up the receiver and listened after pushing a button and the hum was there loud and clear. What do you think?

I think you have a cross somewhere between the w/bl and w/or. Confirm by disconnecting the w/or at the ACS.

-Hal

All my lines are homeruns right back to the punch block and I checked and double checked for proper wiring. Everything looks good. Dave

What have you got from the punch block to the ACS?

Do like I said, confirm that disconnecting the w/or will eliminate the problem.


-Hal

If I disconnect the w/or the phone will not work without power. I am going to double check my wires coming from the ACS. I used a 4-wire modular plug cut on one side and spliced the other side and then punched down onto block.

Your digital phone won't work, but a SLT or butt set will, Hal is trying to eliminate the data pair as your trouble source. This is a good idea.

I did do this with my butt set. I disconnected the orange(power)pair, and hooked up my butt set to the co line only. Buzz was still there. This is why I am so frustrated about this problem. It seems that I have tried everything and I still have that stupid buzz. aaaarrrrgh

You disconnected the w/o pair at the block. What about the line cord you have going to the port?

I used a 4-wire modular plug cut on one side and spliced the other side and then punched down onto block.

Not a good idea even if it does work. Better to press a plug onto a piece of 2pr and punch it down directly.

-Hal


-Hal

You disconnected the w/o pair at the block. What about the line cord you have going to the port?

I used a 4-wire modular plug cut on one side and spliced the other side and then punched down onto block.

Not a good idea even if it does work. Better to press a plug onto a piece of 2pr and punch it down directly.

-Hal


-Hal

Dave, take a deep breath. The CO line only thing is confussing the crap out of me, maybe not others. If you take the station line out of the partner without the data lead do you have the noise? If so eliminate the partner, if you take the "CO" line incoming not going through the partner direct to the jack do you have the noise?

Yeah, me too!

-Hal

Hal, I will redo my wires between the punch block and the ACS, you guilt me into it. I am not sure what you mean by "What about the line cord you have going to the port" please clarify and excuse my ignorance.

Justbill, I'm breathing nice and slow. This is one thing I am not sure I tried. Connecting directly from the interface box to the jack. However, since I brought the phone down to the basement and plugged it directly to the ACS and had no buzz, I figured the co line was clean. No?

Dave, Hal's just trying to determine if it's the wiring or the KSU. You don't want any data leads from the KSU to the jack, period. At that point if you still have the noise eliminate the KSU by going CO feed to the jack. This will help you isolate the cause of your trouble. Length of wire increases noise, so plugging right into the KSU really isn't proving the trouble, also you are eliminating some wiring when doing that, no matter how little. DON'T redo the wires, eliminate them as a source of trouble.

Hey, I got some excellent advice and new knowledge from you guys. I will put it to good use tomorrow and let you know how it turned out. Thanks again. Dave

If I am understanding Dave correctly, it sounds like he has isolated the problem to the cat5 wiring. I am willing to bet that the cat5 is run parallel to the AC somewhere, or crosses a ballast, and is picking up AC hum. Electrical contractor probably ran the phone wiring :nono: . Dave, did you follow justbill's suggestion to kill the AC and turn the breakers back on 1 at a time? What happened?

I think we may be to the point where we need to consider the wire itself. What's the story with it? Who did the wiring, did you inspect or at least see the wiring before the walls were closed, were these two runs that have a problem pulled together and are they next to each other for any distance, are they next to any Romex, is it installed in holes through the studs, metal studs or wood?

Lots of questions I know but there has to be a common denominator here someplace.

Another thought comes to mind and that is can the buzz be heard on the other end by a caller calling you? If so I would like to hear what you are talking about. A 60Hz hum from EMI is distinctly different from the "digital" noise you would get from the data pair.

-Hal

This should tell you something. That is why Hal is saying remove the data pair completely and test with a SLT or butt set. It still could be induction, or still could be the cable, you just have to start eliminating possibilities.