my customer called and had static on line two on a phone system. verizon had been there and said it had an inbalance on the line the customer told me. when i got there i heard static and as soon as i got in the phone room there was no static. i did see that line passes through an alarm. anyway my question is what is an inbalanced line. thanks dave

An imbalance is when one side of the copper pair is longer than the other. This can be caused by one side being open beyond your customer either at a bridge tap or just in the continued count.

An imbalance will cause hum not static. Is there static every time from the phone and not at the DEMARC? Looks like it may take a little more testing to see where it's coming from.

Static is often caused by deteriorated copper and/or splices.

So you have static after the alarm junction, but none before it at the demarc.

Sounds like a bad connection at the alarm or a cable issue between the demarc and phone system.

How close can you get to the Alarm connection? if it's using a RJ31X jack then test it there or if you can get to the alarm terminals, check it there.

i didnt explain well enough. they do have an alarm and they get static off and on. thing is when i got there the static was gone so i didnt get to check if it was at the demark, or before or after the alarm. i think im going to have to wait until it comes back and try to rush over while the static is still there. hard to trouble shoot a line with no symptoms. i called this morning and its been working fine.

What type of alarm is one the line with the static? Security or Fire.

If it's Fire then is breaking code as Fire must have the primary line as dedicated to it alone.

If it's Security, maybe it's doing a line check or something to that effect.

its a security alarm and looks older to me but they seem to think its only about 4 years old. i did advise them to run things by the alarm company. they actually wanted me to check things inside the alarm but here in calif you cant work on alarms with out being certified and i dont know much about them anyway.

In my 30 years+ in dealing with this industry, alarm systems that share a line via an RJ31X jack (which is often not present) are ALWAYS the culprit in these instances. I know, it is impossible to point the blame at the beanie boys, but those dialer units are cheap import jobs and they fail at an alarmingly high rate.

The only thing that you can do to prove your worthiness is to ask your customer to risk letting you bypass the alarm system and wire the line straight-through. Not forever; just for a few days to see if the problem subsides.

As Bill mentioned, the technical definition of an imbalance with regard to telephone circuits is when one wire, say the TIP side, is longer than the RING side. Even a few feet can cause this. This allows it to pick up induced interference from just about anything: AC power, background music, even local radio stations.

Inside a building, this isn't usually a huge deal until you have multiple cables feeding the same line. You did mention two-line phones being used, right? This could mean hundreds of feet of individual station cables adding up through multiple station distributions of that line. An imbalance in such a situation would definitely be an issue.

Dirty/failing relay contacts on an alarm dialer can create an artificial imbalance on a heavily-loaded line. This comes from resistance on only one side of the telco that isn't 100% equal to the other. As much as I hate to side with Verizon, they might be correct on this one if they did their testing correctly.

i know alarms can cause trouble but i didnt know it was the dialer at fault. maybe i will suggest putting the alarm on line 3 for a few days and if the problem moves to three we pegged it. thanks for the info.

Be sure to let the alarm company know the new number or you'll cause all kinds of problems with the alarm