Dophiのブログ

    A big disaster just happens during this Xmas season. The post-service assistant gets a lot of ERS2500 for replacement because of power supply failure recently.  I was so surprised of this high failure rate of ERS2500 and looked for solutions or bulletins which might explain this weird situation.  Finally, a bulletin was found and it mentions the root cause of it.

    Only ERS 2526T and 2550T are impacted by this abnormal failure. This abnormal failure rate is caused by a defective capacitor used in the integrated power supply of some previously built units. The symptom of this problem is that the switch loses its power and cannot be powered up again. The ERS 2526T and 2550T switches which were produced before July 1st, 2007 have the risk of this issue and may work well for many months or years before failing.

    The ERS2526T switches that are affected by this power supply capacitor issue are contained in the following serial number ranges:

LBNNTMJL44001D ~ LBNNTMJL4400ZZ
LBNNTMJL440100 ~ LBNNTMJL4401ZZ
LBNNTMJL440200 ~ LBNNTMJL440292
LBNNTMJL440303 ~ LBNNTMJL4403ZZ
LBNNTMJL440400 ~ LBNNTMJL4404R2

    The ERS2550T switches that are affected by this issue are contained in the following serial number ranges:

LBNNTMJL46001C ~ LBNNTMJL4600NP
LBNNTMJL4600WR ~ LBNNTMJL4600ZZ
LBNNTMJL460100 ~ LBNNTMJL46016D

Verity the serial numbers of ERS2526T and ERS2550T and contact with your service provider. This is what I recommend. 

2009-Sep-24 Update:

The new bulletin has been announced,  Nortel provides contact lists and the procedure of replacement.

This is the link of New Tech Bulletin:  http://www116.nortel.com/pub/repository/CLARIFY/DOCUMENT/2009/26/024699-03.pdf