atcomsystems.ca/forum Forums Thread Like Summary - TDA50G Multiple Bad Digital Station Ports

Hello,
Our customer has a 6 year old TDA50G that had multiple digital station ports that quit working.
On Aug 10th 2 consecutive ports on the second 5172 station card quit working X117-118.
No display on the phones, no lights would work except the MW light would stay on.
Replaced the card with new and they worked fine.

Two weeks later one of the ports on the first 5172 card quit working X101.
Same as above.

Now two more weeks later one of the original ports that quit working on the second card, quit again X118.
Total time this port worked after card was replaced was about 4 weeks.

These ports themselves quit working and do not work when a phone is plugged directly into the 5172 card RJ11 station ports.

These extensions are serviced by a 4 year old underground cable and reside about 350ft away from the KSU in a different building.
This cable does have lightning protection on each end of the cable and is run in conduit between the buildings.

I plan to examine the the cable terminations and test resistance on these pairs on my next trip out.

I was mainly interested in finding out if the 50G systems have any history of station port issues as they got older.

We installed a number of these 50G systems through the years and so far have never had a port go bad on any of the others.

I do not see any corrosion on either of the original 5172 boards or connectors but there was some dust inside the cabinet.

Any suggestions would be Much appreciated! Thank You!

Were there any reports of voltage spikes on the AC line, recent thunder/electrical storms?

I would check the DC of the power supply to make sure there is no AC/DC ripple or the regulator is failing and it's output is over voltage.

I pulled up the TDA50/G Installation manual to first check the allowable distance for wiring.

The smallest figure quoted for using "other" PTs or a DSS Console is 458ft using 26AWG wire, so you are definitely good there.

Is the conduit steel, or PVC? Is it possible water could have entered the conduit and caused damage? Is there anything else run in the conduit besides telephone pairs? Hopefully there is nothing over 24 volts.

You might consider ringing out the pairs in the conduit to check for oddly high resistance as well as intermittently shorting pair(s).

Check the static/lightning protection unit closest to the PBX. Repeated static, spikes, and electrical activity hits will weaken the MOVs in surge protection units over time and eventually break them down.

Give it the "smell" test for burned parts as well as physical inspection.

If all this checks out to be okay, I think you may have to call Panasonic support. Have your Dealer ID # handy.

Unfortunately in a few more months the world of Panasonic PBX systems will end. I have no idea how dealers will continue to support existing product after the final cut off date.