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harrypotter
2011-09-06, 02:38 PM
Dear Experts,

Anyone has this alarm, 7745**, CHANNEL FAILURE RATE ABOVE DEFINED THRESHOLD." [02 01 00 00 00 00 00 00 00 00 02 85d]

I am getting this alarm in our 2G network. Please advise.

alb_elezi
2011-09-06, 04:34 PM
In this forum was posted this file, give it a try

KoJaa
2011-09-06, 06:47 PM
Dear Experts,

Anyone has this alarm, 7745**, CHANNEL FAILURE RATE ABOVE DEFINED THRESHOLD." [02 01 00 00 00 00 00 00 00 00 02 85d]

I am getting this alarm in our 2G network. Please advise.

If you look at NED you would find a description of that alarm detailing the specifics of this line [02 01 00 00 00 00 00 00 00 00 02 85d].

If i'm not mistaken that alarm affects SDCCH on TSL 1 with 85% failure rate.
If it is intermittent, you could try resetting the sector first. If the alarm re-occurs transfer SDCCH from tsl-1 to tsl2, this usually solves the problem.

harrypotter
2011-09-06, 07:26 PM
If you look at NED you would find a description of that alarm detailing the specifics of this line [02 01 00 00 00 00 00 00 00 00 02 85d].

If i'm not mistaken that alarm affects SDCCH on TSL 1 with 85% failure rate.
If it is intermittent, you could try resetting the sector first. If the alarm re-occurs transfer SDCCH from tsl-1 to tsl2, this usually solves the problem.


Yes.. I already transferred the SDCCH to TS 2, but alarm still occurs. Any recommendation?

alb_elezi
2011-09-06, 08:11 PM
Yes.. I already transferred the SDCCH to TS 2, but alarm still occurs. Any recommendation?

SWAP the TRX with another one in the same Site, if the problems follows the TRX than you have a faulty TRX. Try also to SWAP other cell specific BTS HW parts one by one in the same site and this way you will find the faulty unit.

KoJaa
2011-09-07, 03:03 AM
Yes.. I already transferred the SDCCH to TS 2, but alarm still occurs. Any recommendation?

did the alarm happen on the old TSL1 or it followed on TSL2? if it happened on TSL1 then you probably have a HW problem then you may follow alb_elezi's recommendation. Quick fix would be to lock this tsl.

If it happened on TSL2 then try removing the SDCCH tsl and changed it to TCH, hopefully you have enough sdcch left after removing this tsl to avoid sdcch congestion. If the alarm did not occur then you are now ok.

Check also interference KPI, if it is high then you might have to retune the frequencies.

Check also the history of this alarm on that specific site, zeoh:2011-9-5:bcf=??,nr=7745; if the alarm points to other tsl randomly other than sdcch then forget about everything, lock the trx then do alb_elezi's recommendation.