ISDN BRI - TLU79 gets blocked

[TheCurious]

Hi folks,

I have an installation where BC12 SP6 system is connected to ISDN BRI lines via TLU79. ISDN lines have bad quality, and there are lot of alarms which appear and disappear in a short time (local telecom claims that "everything is fine" with their lines).
Alarms are:
269 DIGITAL TRUNK, LOSS OF FRAME SYNCHRONIZATION
274 DIGITAL TRUNK, CLOCK MALFUNCTION (SLIP)
303 DATA LINK ALARM

After some time, large number of errors is causing that trunk gets blocked. Than I remotely restart program units for ISDN (SLP60, TLP60, ADEP), and traffic starts again.
I played a lot with SCEXI, and changed different combinations of sync priority between all 4 ISDN interfaces on board, but without success.

I understand that there is a counter that counts line errors. If there are too many errors in a short time, trunk gets blocked. Later, when line errors are finished, trunks on TLU79 remain blocked.

Is there a possibility to change this behaviour (so trunk comes back to service when errors are over)?
Is it possible to increase counter value to some unreasonably high value, so trunks do not get blocked ?

Thank you in advance,

The Curious

 

[doktor]

The grunding of your MD110 should be done according to the installation specifications. Ground with at least ø 10 mm cable to ground connector.


///doktor
____________________________________

http://www.kandu.dk/spg153996.aspx

 

[TheCurious]

OK Goldstar Doktor,

I will try to improve the grounding, but I suppose that it will not solve the problem.
What I had in my mind is software solution.
From my experience I know that BP250 systems never have problems with BRI ISDN, and MD110 are very sensitive to BRI errors.
What is your experience ?

Best regards,

The Curious

 

[doktor]

I do not know BP250, so maybe you are right.
Goldstar, I used to work with. Now 23 years with MD/MX.

///doktor
____________________________________

http://www.kandu.dk/spg153996.aspx

 

[TheCurious]

OK Doc,

So you had the same BRI problem with MD110 and solved it by grounding the PBX ?

The Curious

 

[doktor]

Yes, it happened. Sometimes the hardware for the BRI (PROM) needed upgrading.

///doktor
____________________________________

http://www.kandu.dk/spg153996.aspx

 

[TheCurious]

Tak Doktor

The Curious

 

[doktor]

With the alarms shown:

269 DIGITAL TRUNK, LOSS OF FRAME SYNCHRONIZATION
274 DIGITAL TRUNK, CLOCK MALFUNCTION (SLIP)
303 DATA LINK ALARM

I guess that your TELCO has a problem...

///doktor
____________________________________

http://www.kandu.dk/spg153996.aspx