atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Telephone Repairs & Equipment Cortelco phone issues

Hello, I am having an issue in troubleshooting cortelco phones. The problem I am coming across is that the phones are giving out static, then the user cannot receive calls, disconnecting phone calls, muting phone calls,and at times the keypad does not work. This also happens with any new replacements I used to replace the phone. I take the phones elsewhere to a good jack and no issue. I re-punch the jack and any connections to the IDF and to the mdf. I tone the line for any shorts and see none. Any ideas?

That would tell you that the phone is not bad. You really need to get a proper working set of tools-hopefully a working butt set with a P Phone adpater. Cortelcos are analog telephones...as easy to troubleshoot as it gets. The problem you describe is a line issue. Go to the DMarc, lift the building jumper and retest. No good there you have a carrier issue. Bad when you put the jumper back on the lugs you have a building wiring issue.

"Do you have a meter, and do you know how to use it to find telephone wiring faults?" he asked for the umpteenth time...

Sorry if I do not respond quickly. I can get a hold of one, will try it out never really tested a phone line using a meter other than to see the 48-50 volts.

I think what Arthur is referring to is things like loop loss, resistance, shorts etc. What you can do is on the station cable unplug the phone. Disconnect the dial tone put the meter on ohms. Take one test lead put it on the station cable tip put the other lead on the ring side did the reading change? Take the test lead off the ring side touch it to a known good ground did the meter register anything? Now move the test lead from the tip side to the ring side leaving the other lead on ground, did the meter register anything? Go to the jack short the tip and ring together. Go to the station block and measure the resistance between tip and ring, what does it read?

Will do so ASAP ty! This particular issue happens a lot after the painters and floor cleaners go through the rooms. Just found out the painters were not covering the jacks with painters tape (or anything) at all.

I would let someone know if you aren't careful with cleaning products your stuff could look like this.

https://sundance-communications.com/forum/ubbthreads.php/galleries/594158/Why_don't_my_phones_work?#comments

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That nice green color makes for better continuity.

Sad part is the hotel that is in declared bankruptcy and closed before I could fix it. Then again had I fixed it I might not have been paid.

"I think what Arthur is referring to is things like loop loss, resistance, shorts etc. "

Yes, what I was referring to, and trying not to be too sarcastic or obvious, is that trouble shooting electrical wiring is an art and a science. One cannot expect others, separated by distance, to help find the fault. It is a personal task.

When I used to teach telephony, and specifically trouble-shooting, the first thing I would ask the new class of students was "When you go to the doctor, regardless of your complaint, what are the very first things he does when examining you?"

SOMETIMES the answers were consistent. "Remove extraneous garments. Take my temperature. Take my blood pressure. Take my height and weight. Measure my blood sugar and 02 levels." From that beginning, I would attempt to draw an analogy to trouble shooting.

Remove equipment and source from pair.

Use a meter and check for metallic faults. Isolate portions of the pair that do not exhibit faults.

Use more sophisticated equipment to find more sophisticated faults. You need a "brown meter," an open meter, a Dynatel fault meter, a Hot Set, and a good tone injector/probe combination. A tool box equipped with test leads that have lots of connectors for various terminal blocks is essential.

Example: A corroded open will show up on an "open meter" as an unbalanced pair. That will cause static.

A combination of intelligence, experience, a mental visualization of the infrastructure, proper tools and a scientific approach will always lead to a satisfactory conclusion.

As an old foreman used to say "It's only battery and ground."

Indeed! That’s the problem. Painters find it difficult to cover them resulting into our loss. It’s fine sometimes, but usually this is the case.