sundance-communications.com/forum Forums TDM Business Telephone Systems Samsung Telephones & Systems "Plug out" disconnects on PRI OS500

OK, I'm having a chronic problem on an OS500 Rel 2(ver. 2.75b) with a PRI circuit connected to TEPRIa card. Customer is experiencing disconnects on established calls at random times. They will be talking and suddenly call will drop and "plug out" will be displayed on the screen. When I check the error log I see a lot of MJD01's and MJD02's, (loss of sync). Carrier is pointing fingers at the Samsung. Anyone else seen this before?

Do you have a CSU in place?

Waht Software is on the TEPRI?

Damn, Wrichey does know his stuff - I started typing the same thing. You should definitely have a CSU in place - preferably an Adtran ACE if we are talking about a plug straight out to the telco.

Yes, Adtran CSU is in place. Software on TEPRIa card is 4.21.

I've tested the system without the Adtran in the circuit, but same problem.

What slot is the Tepri in? How many power supplies?

If in slot one and you have two supplies then it's time to trap the T1 and watch it for a while. The CO will always blame the system first. Is this a full 23 channels or partial?

They should be set for high to low and you from low to high to avoid glare (not that this is the problem). If this is an old CO or a rural one then you may have to adjust a few settings.

How long was it working before sync errors? Did they recently upgrade the CO?

Sorry for all the questions but there is a lot of research that needs to be done.

Ask all the questions you want, I don't mind at all.

TEPRIa is in slot 1, full 23 channels, set to NI2. Two power supplies. System is fully loaded with 2-16dli's, 5-16sli's, and 1-Svmi8e.

They are set from high to low and I'm set from low to high. I'm not sure of the age of CO, I think its a 5ESS, carrier is Telepacific, but definitely not rural as its in Upland, CA(east Los Angeles).

System has been in a year and has had random sync errors from the beginning. We've had them(Telepacific) look at it and they've always found something wrong in the field and fixed it, only to have the problem show up again sometime later. Last call I received from them they said they were seeing d-channel "protocol" errors. We went up there earlier this week to take a look at the error logs in the Samsung. Showed a bunch of sync errors, and a few yellow and blue alarms(nothing new there). Always very brief and always clear on their own. Talked to Samsung and they pointed out that the software level they were on(2.69) was not compatible with the TEPRIa software(4.21) and recommended upgrading to at least 2.72. I was skeptical but, I went there early Friday morning and upgraded them to 2.75b anyway, reprogramming thru KMMC from scratch! Error log was clear for the 2 hours I was there after reprogramming. By the time I got home(I live 1&1/2 hours south in San Diego)the problem recurred.

I've been putting in PRI's for a long time so I'm very familiar with the finger pointing game. In my experience its almost always the carrier, never the switch. I'm thinking of installing an older Adtran ESF csu ace since it has a screen and error tracking ability to try and catch errors coming from the direction of CO.

Thanks for the help BTW. I really appreciate it.

Just for grins lets consider that two PSUB's can run 120 stations max. Have you done a count on used psu's? You are scary close to the limit if not over.

That would explain the "plug out" issue and disconnect. Maybe a supply has become weak.

Still thinking though...

Yes, I'm following your train of thought on the PSUB's. I'm checking the database on my laptop right now, but MMC806 isn't showing which cards are on which PSUB, like it does through KMMC. I can assume that one of the PSUB's is responsible for 64 stations if I do the math myself. I guess I can call Samsung tomorrow and see if they think thats too close. I've heard this complaint of "plug out" on disconnect on one other system of ours, and only once. That system has 5-16 port station cards, a TEPRIa, MGI16 and SVMi8. Slot 9 open. Should be fine on power. I need to ask Samsung again what "plug out" could possibly mean in this senario.